6thGradeEssentials
Portal
Portal
Portal
Learning Check
6th Grade Science Essential Vocabulary & Concepts
  • Learning checks are given weekly to measure student growth on essential concepts and vocabulary throughout the year.
  • These are not graded, students are to track their own scores in their notebooks in order to see growth over time.
  • It is expected that students will see low scores that become higher scores over time.
  • Students should continue to refer to this page, take the practice learning check often, and play all of the quia games for all units over the year.
A01 Process Skills & Measurement
Picture Core Knowledge or Concept
Jane Goodall Science is the process of explaining the natural world.
observe
 Observing is using your senses to gather information about the world.
qualitative
Qualitative observations describe using words, diagrams, or models.
measure
Quantitative observations measure using numbers.
inference
Inferring is making sense of your observation.
prediction
Predicting is making an inference about a future event

model
Models help people understand things that they cannot observe directly.

communicate
Communicating is the process of sharing ideas and information with other people.

metric system
Metric System (International System of Units, SI) a system of measurement based on the number 10.
  •   A meter is the unit used to measure length, or the distance between two points.
  •   A liter is the unit used to measure the volume of a liquid or the amount of space it takes up. 
  •   A gram is used to measure the amount of matter in an object. 
  •   Degrees Celsius measure temperature.

A02 Scientific Method
Picture Core Knowledge or Concept
Jane Goodall Scientific Method a system for investigating the universe..
observe
Problem: Always asks a question.  The problem guides the experiment

qualitative
Background Research: Find out what we already know about the problem, including our own personal knowledge and research on the topic.
 
prediction Hypothesis: A testable statement that “answers” the problem.  This is usually written in an “if, then” format.  It is based on the background research.

inference
Experimental Design: Describes how the experiment will be performed.  It     is written in a list format and contains the following sections:

variable A. Variables:  The three types are:
  1. Experimental / Manipulated / Independent: the one you change
  2. Measured / Responding / Dependent: the one that is observed data
  3. Controlled: the ones that stay the same
model
B: Procedures: a numbered list of exactly what you will be doing.
C.  Materials: a numbered list of exactly what you will be using.

metric system
D: Trials: how many times you run an experiment.
communicate The results section is the data from the experiment.
It can be a table, graph, or chart.
bright idea An analysis is the explanation of the data of an experiment.
A conclusion summarizes the experiment referring to the hypothesis and states how the experiment may be changed.
Van De Graaff The Experimenting or experimentation is a method of testing scientific ideas.
pseudoscience The PseudoScience is not science. It does not follow all of the steps of the scientific method. It is often used to trick people.
wheel The Technology is the creation of goods and services for human use. It uses a method called theDesign  Cycle.
A03 Motion
Picture Core Knowledge or Concept
speed gun  An object is in motion when its distance from a reference point changes.
runners
Average  speed is: total distance in a given or total, time.  (Like from the start to finish line.)
(The opposite is instantaneous speed, speed at a given moment in time like on a roller coaster.)
Speed does not give a direction travelled. 
(Speed = Distance Time)
missile
Velocity is speed in a given direction.

prediction Vectors or rays are arrows that can show motion and forces.
A04 Acceleration
Picture Core Knowledge or Concept
archery

Acceleration is the rate (how fast) at which velocity changes 

  1. speeding up (faster if Speedend - Speedstart is positive)
  2. slowing down or deceleration (slower if Speedend - Speedstart is negative)
  3. turning (direction)
Opposite: Constant velocity is when speed and direction do not change.
accelerometer

An accelerometer measures changes in acceleration or jerk.

Electronic acelerometers are used in cars to set off airbags and in runners' speedometers.

LadyBug Motion Vectors or rays are arrows that can show velocity and acceleration.
formula
The formula for acceleration is (final speed - initial speed) / time. or ( Speedend - Speedstart ) ÷ time
Change in speed is (Speedend - Speedstart)
formula
Galileo Gravity
Scientist

Galileo Galilei experimented with gravity by dropping things from a tower, rolling things down ramps, and observing the planets and moons of the solar system.

A05 Forces, Inertia, & Newton's 1st Law
Picture Core Knowledge or Concept
force
A force is a push or a pull.
net
Net force is the sum of forces acting on an object.
balanced
balanced forces: are equal and opposite.
They do not cause motion

unbalanced
unbalanced forces: are not equal.
They can cause things to move.
arrows
Force arrows show the magnitude and direction of a force.
The width or length can show strength.
inertia
Inertia is the tendency of an object to resist change to its motion. An object's inertia is related to its mass.
mass
Mass is the amount of matter in an object.

Matter is anything that has mass and volume (takes up space.)
Inertia
Newton’s first law of motion (aka, The Law of Inertia) states that
"an object at rest remains at rest and an object will remain in motion unless acted upon by an unbalanced force."
freebodydiagram
Free Body Diagrams: a standard diagram that shows all of the forces acting on an object.
The object is a box at the center with arrows pointing towards it from the direction of each force.
newton
Scientist

Isaac Newton was a mathematical genius who invented new types of math related to motion and forces. Evidence suggests that he may have had a form of autism.

A06 Newton's 2nd Law: f=m*a, Friction, and Gravity
Picture Core Knowledge or Concept
feet on scale
Weight (Mass * Acceleration due to gravity) is the measure of the force of gravity upon an object.
(i.e. you weigh less on the moon, but your mass is the same.)
slide
Friction is the force that one surface exerts upon another.
(i.e. sliding on gravel slows you down versus sliding on ice, rolling on wheels, a fluid water slide, or static: not moving).

Its force always acts in the opposite direction to motion

Friction's strength depends on
  1. ​the type of surface (like rough, smooth, sticky, slimy, etc)
  2. How hard they are pressed together
4 types:

fluid friction: liquids and gasses
sliding: when one or both surfaces are moving or rubbing together
rolling: when one or both surfaces are spinning
static: when neither surface is moving
Graavity Well
The law of universal gravitation states that the force of gravity acts between all objects (matter) in the universe (everything, everywhere).

spacewalk
Gravity is the force that pulls objects towards more massive things (like Earth).

Gravity's strength varies by
  1. Distance: closer is stronger
  2. Mass: more mass has more gravity.
On Earth's surface, things in freefall accelerate 9.8 m/s/s unless it is slowed by air resistance.
http://www.etorgerson.net/Images3/asteroid-hit-earth.jpg
Newton’s Second Law of Motion states that the net force of an object is equal to the net product of it acceleration and its mass.
(i.e. a speeding car has more impact than a blowing leaf crashing into a wall)

(Force = Mass * Acceleration)
einstein
Scientist

Albert Einstein was a mathematical genius who related time, space, gravity, and mass in his theories of special relativity (Time and space) and general relativity (gravity, space, and mass.) He also defined the speed of light as a universal speed limit and related energy and matter with e=mc2.

A08 Newton's 3rd Law: Action-Reaction & Momentum
Picture Core Knowledge or Concept
Newton 2 Momentum ( M ass * V elocity), Is related to kinetic energy or moving energy.
pool balls
The law of conservation of momentum states that total momentum of any group of objects remains the same unless an outside force acts on the object.
  1. If pool balls collide, the combined momentum is the same after they hit.
  2. Motion can be transfered from one object to the other.
  • exception: In a car crash, some of the energy is lost into the change of shape. This is why cars are built to crumple.
prediction
Newton’s third law of motion states that if one object exerts a force on another object, the second object exerts a force of equal strength in the opposite direction on the first object.
  1. action = reaction or if you push me, I push you back.
  2. When the rocket blast pushes down, the rocket reacts by going up.
gb Scientists

Robert Goddard, the father of rocketry in the early 20th century

Wernher von Braun, developed the Atlas rocket for the United States. His rockets were powerful enough for NASA's space program and, along with competing Soviet scientists created intercontinental ballistic missiles that could have destroyed the world.
pugh
Technology

Pugh Charts: are used to check if a design meets the specifications (requirements) of a design.
Usually used to compare designs (columns) against each specification (rows.)
pugh
A09 Energy
Picture Core Knowledge or Concept
energy
Energy Energy is the ability to do work or cause a change.

The unit of energy is the Joule.
Kinetic
Kinetic energy is the energy of motion. It depends on mass and velocity.
(i.e. a book falling)

Potential
Potential energy is energy that is stored and ready to be released.
(i.e. a book on a table ready to fall)
  • Springs store elastic potential energy
  • Height stores gravitational potential energy.
Potential Energy = Weight * Height
(weight is in newtons, height in meters.) formula for gravity (Earth's = 9.8 m/s2)
Forms of Energy
Forms of energy and their sources
  • mechanical (motion): wind, water, machines, animals
  • thermal (heat): buring, the sun, electric heaters, chemical reactions
  • chemical (molecular bonds): chemical reactions, molecules
  • electrical (electrons): lightning, chemical reactions,  solar cells,  generators
  • electromagnetic(light, radio waves, x-rays, etc.): the sun, lights, heaters
  • nuclear (radiation). atoms breaking down or being made
Work
Work is the transfer of energy between objects.
(Like a force that makes an object move.)

work = force * distance
(force is in newtons, distance in meters.)

The unit of work is the Joule.​
fire starter
Energy conversion occurs when one type (form) of energy is changed into another.
(i.e. electricity into sound, motion into heat, etc.)

newton's cradle
The law of conservation of energy states that energy can neither be created nor destroyed.

Einstein's theory e=mc2 says that energy (e) can be converted to matter (m) and vice versa (and back again).
Fermi
Scientist

Enrico Fermi, the father of American Nuclear Physics at the University of Chicago. His work is continued in the Manhattan project, Argonne National Labs, and the Fermilab Accelerator in Batavia.
A10 Pressure
Picture Core Knowledge or Concept
force over area
Pressure  is a force spread over an area. 
Pressure (Force ÷ Area)

Pascal (Pa)" the unit of pressure in Newtons/meter2

(i.e. the pointy end of a stick hurts more than the side of the stick)
squish
Fluid a substance whose shape can easily change.
Fluids are usually liquids or gasses.

In fluids, the particles (molecules and atoms) are not locked together and can move past each other.
depth
Pressure increases with depth and decrease at higher elevations or altitudes
This is because of the weight of the fluid above.

In space, there is no pressure. It is a vacuum.
puffer
Pressure in fluids are transmitted or distributed in all directions.

Because the fluids in our body have the same pressure, we are not crushed by air pressure or water pressure in the ocean.
fluidpressure
Pascal’s principle states that when a force is applied to a confined fluid (liquid) an increase in pressure is transmitted equally to all parts of the fluid.
heart

Force pump is a device that causes a fluid to move from one place to another by increasing the pressure in the fluid.

Lungs and hearts works because fluids move from areas of higher pressure to areas of lower pressure.

Because blood does not leak out of the system, it is called a closed system.

hydraulics
A hydraulic system multiplies a force by applying the force to a smaller surface area. 
It usually uses oil or water, fluids that do not lose force when compressed.

Systems that use air, like air brakes or air nailers are called pneumatic systems.

(i.e. your foot on a brake pedal can stop a truck)

Pistons or plungers are the devices at the ends of some hydraulic systems that transmit force outside of the system

hydro- Greek root for water
density
Density is the amount of matter in a given space.
Floating and sinking
Buoyant force: The upward force exerted by a fluid on a submerged object that is less dense.
The property of an object to float or sink is called buoyancy.
archimedes
Archimedes' Principle states that the upward buoyant force exerted on a body immersed in a fluid is equal to the weight of the fluid the body displaces.
bernpas
Scientists

Blaise Pascal,(1623-1662) French mathemetician and religious philosopher whose interest in the mercury barometer led him to climb mountains and experiment with pressure. He invented mechanical adding machines that predicted computers.

Daniel Bernoulli (1700-1782) Swiss mathematician whosework with moving fluids is the basis of today's work with airplanes, submarines, water systems, and hydraulics.

B01 Heat
Picture Core Knowledge or Concept
thermometers
Temperature is a measure of the average kinetic energy of the individual particles
(i.e. two units of temperature are degrees Fahrenheit (°F) and degrees Celsius (°C).
absolute zero is the lowest temperature possible. atoms stop moving.
TE
Thermal energy is the total energy of all of the particles in a system.
boiling
Heat is thermal energy moving from warmer objects to cooler objects.
conduction
Heat is transferred (moved) in three ways:
a.     Conduction - the process of heat being transferred from one particle of matter to another without the movement of matter itself. (i.e. by touch)
lavalamp
b.     Convection - the movement that transfers heat by the movement of currents within a fluid.
(i.e. a fire’s heat rises & warms the air above, cool air falls)
radiation
c.      Radiation - the transfer of energy by the electromagnetic waves.
(i.e. heat from a fire warms your hands and face from a distance)
conductor
Conductors are materials that conduct energy well.
(i.e. metal pot handles, copper wire)
jacket
Insulators are materials that do not conduct energy well.
(i.e. pot holders, plastic coating on wires)
phases
  The states of matter are:
  1. solid : lowest energy- has a definite volume and a definite shape.
    (i.e. spilled rocks look the same as they do in a glass)
  2. liquid: more energy- has a definite volume, but takes any shape.
  3. gas: even more more energy- fills any volume and shape
  4. plasma: most energy- Atoms lose electrons and act like a gas.
B02 Atoms
Picture Core Knowledge or Concept
atom
An atom is the smallest particle of a substance (matter).


deuterium
There are 2 regions of an atom

The nucleus in the tiny center of the atom is made of protons and neutrons.

The electron cloud is the outside area made up of mostly empty space.
helium
Protons are tiny positively charged particles.
Neutrons are neutral (no charge).
isotopes
Atomic mass is the total number of an atom’s protons and neutrons.

Atomic number is the number of an atom’s protons only. This number is used to classify types of atoms.
electron Cloud
Electrons are negatively charged particles that orbit around the nucleus in the electron cloud. They are much smaller than protons and neutrons.
In a neutral atom, there are the same number of electrons as protons.
Valence electrons react with other atoms. Thry have the most energy and are the furthest from the nucleus.
copper
 A pure substance is stuff made of only one kind of matter with definite properties.  (i.e. sugar, salt, iron, & copper)
carbon
Some pure substances, called elements, cannot be broken down into other substances by any chemical means.  (i.e. iron, copper, gold, carbon, & chlorine)
periodic table
The periodic table an arrangement of the chemical elements by increasing atomic number, which displays the elements so that one may see trends in their properties. 
group Elements in the same group (column) react similarly.
Group1 and 2 metals react strongly with group 7 elements. Group 8 gasses are unreactive.
MarieCurie
Scientist
MarieCurie (ne: Sklodowska): the first person to receive 2 Nobel Prizes for her work in radioactive particle physics (1903) and chemistry (1911). Her work paved the way for modern nuclear technologies in  medicine, power,  and the military.
B03 Matter and Molecules
Picture Core Knowledge or Concept
aceticAcid
A molecule is a group of atoms that are joined together and act as a single unit.
(i.e. a water molecule is made of 2 hydrogen atoms tied to 1 oxygen atom: H2O.)
H20
A chemical formula (molecular formula) is the recipe for what is in a molecule.
The element symbol Letter goes before the Number of atoms, so H20 has 2 hydrogen & 1oxygen.

A structural formula is a way to show how molecules are put together. Lines represent bonds between atoms.

bonds
Atoms are held together in chemical bonds by sharing, gaining, or losing electrons.

A compound is a substance made of two or more elements.
mixture
A mixture is two or more substances found together.
salt dissolving
Solution is a very well-mixed mixture of two substances that keep their properties.
(i.e. sugar water vs. salt water)
A solvent is a liquid and solute is a solidlike a powder.
beryllium
Characteristic  properties are qualities of a substance that never change and can be used to identify the substance.
They can be physical properties and chemical properties.
crystal
Physical properties can be any property used to characterize matter and energy and their interactions. 
They can be observable using instruments or the five senses.
(i.e. crystal shape, color, texture, hardness, bends or breaks, density, resistance to water and fire, conductivity or heat or electricity, melting/boiling points)
density
Density of a substance is its mass per unit volume. (mass / volume)
Mortar Physical changes change the form of a substance, but not its identity.  (i.e. crushing, folding, freezing, boiling, dissolving, mixing, cutting, twisting )
Venter And Collins
Scientist
 Craig Venter and Francis Collins decoded the DNA molecule of several life forms, including humans.DNA is one of the largest molecules of all and holds the instructions for how to build the molecules of living things.
B04 Chemistry
Picture Core Knowledge or Concept
chem Chemical properties are how a substance reacts and changes with other substances under which conditions.

reaction
In chemical changes / reactions one or more substances combine or break apart to form new substances.
(i.e. burned wood becomes charcoal, water vapor, and carbon dioxide gas)

burning
Chemical equations show the reactants and products of a reaction on either side of an arrow showing the direction of the reaction.
  • 2 H2 + O2  --> 2 H20
  • Reactants are the chemicals before the reaction (right side 2 H2 + O2)
  • Products are the chemicals after the reaction. (left side 2 H20 )
h2cl2
conservation of mass: matter is neither created nor destroyed during a chemical reaction.
A balanced chemical equation shows this by having the same number of atoms on both sides of the equation.

instant cold pack

Bonds store energy that is related to thermal energy.
  1. Exothermic reactions give off heat making substances warmer. (In instant heat packs, iron powder (Fe) rusts when it is exposed to oxygen.
  2. Endothermic reactions absorb heat making substances cooler. (In instant cold packs, ammonium nitrate NH4NO3reacts with H2O and uses thermal energy to break bondsmaking it colder.)
reactionRate
Reaction rates are the speed that a substance enters into a chemical reaction. Reactions can be controlled using
1.    concentration: how much chemical is present (the flask limits oxygen)
2.    surface area: how much is exposed to the reaction (powder versus block)
3.    temperature: thermal energy often speeds reactions
4.    catalysts/enzymes: molecules that help the reaction
5.    inhibitors: molecules that slow reactions
mitochondria
Scientist

Hans Adolf Krebs- Nobel Prize winner- discovered how energy molecules are made in living cells in the citric acid or Krebs cycle.
B05 Waves
Picture Core Knowledge or Concept
tidal wave
A wave is a disturbance that transfers energy from place to place. (i.e. jump rope)

Two categories of waves are:
a. Mechanical Waves- require a medium to travel through. (i.e. water waves in a pond)
b. Electromagnetic Waves- do not need a medium. (i.e. light and radio waves.)

A medium is a material through which a mechanical wave travels.
Waves Two types of waves are: TransverseWave

a. Transverse - waves that move the medium at right angles to the direction in which the waves are traveling.

The top is a crest and the bottom is a trough.
(i.e. like a snake wiggling side to side in an ‘S’ shape)
speaker
b. Longitudinal - waves move the particles of the medium parallel (the long way) to the direction that the waves are traveling. CreatingALongitudinalWave

Compression is close together and rarefaction is spread out.
(i.e. like a slinky getting squeezed and then opening up)
properties
frequency
Properties of waves are:Transvere Versus Longitudinal Waves

a. Amplitude is the maximum distance the particles of a medium move away from their resting point as a wave passes through the medium.


b. Wavelength is the distance between two corresponding parts of a wave.


c. Frequency is the number of complete waves that pass a given point in a certain amount of time.

d. speed is the distance travelled divided by time.

 speed = wavelength x frequency (= distance / time)
interference
Interference between waves that meet.

When two waves pass through each other they can add together to make a larger amplitude or cancel each another out
Joseph Fourier
Scientist

Jean-Baptiste Joseph Fourier (1768-1830) was a French mathematician who worked on how frequencies are related by developing the Fourier Transform/
UltraSound
Technology

Sonograms use sound waves that pass through the medium of the body to make pictures.



B06 Sound
Picture Core Knowledge or Concept
trumpet
Sound is a disturbance that travels through a medium as a longitudinal wave. Sound begins with a vibration.
Sound waves can travel in solids, liquids and gasses.
Waves An echo is when sound waves reflect off of an object
speaker
Sound waves spread out and can diffract or bend around objects.
amplitude
The loudness of a sound depends on the amplitude or energy of its wave.
Intensity is the measure of the energy of a sound wave over an area.
The unit of loudness is the decibel dB.
distance
Distance can make sounds less loud.
As sound waves spread out, they have less energy per unit of area, so they sound softer.
marimba
The pitch of a sound depends on its frequency.
The unit of frequency is the Hertz or Hz.
Humans can ususally hear from 20Hz to 20,000 Hz.
rail
The speed of sound is different in different materials.
Sound generally goes slower in gasses and faster in solids.
Speed can change with elasticity, density, and temperature.
A sonic boom is when something goes faster than mach 1, the speed of sound.
doppler
Doppler effect moving sound sources can make frequencies appear higher or lower by compressing or spreading out waves.
Robert Moog
Scientist / Engineers

Robert Moog manufactured early synthesizers by creating sound modules that could generate or change sound waves.
synth Technology

Synthesizers are musical instruments that simulate or create the sounds of instruments by changing the shapes of sound waves.

B07 Electromagnetic Waves
Picture Core Knowledge or Concept
em wave
Electromagnetic waves carry both electrical and magnetic energy.

In a vacuum (outer space), they travel at the speed of light, 300,000km / second.

Electromagnetic radiation is the energy transferred by electromagnetic waves.
Wave model Wave Model of Electromagnetic Waves (Light)

EM waves act like transverse waves. By using polarized filters or lenses, waves that are vibrating in certain directions can be blocked like a rope waved through a picket fence.

photon
Particle Model of Electromagnetic Waves (Light)

A photon a tiny packet of light that acts as both a wave and a particle.
They are created when electrons lose energy or when protons fuse in the sun.
They can create electricity when they hit electrons in solar panels.

light ray
 A ray is a straight line used to represent a light wave in diagrams and in mathematics.
spectrum
The electromagnetic spectrum is the entire range of frequencies and wavelengths of electromagnetic waves including the visible spectrum that we see as colors. (i.e. radio waves, microwave, infrared, visible light, ultraviolet, x-rays, gamma rays.)
interference
Radio Waves:

Long waves with low energy, these are used in AM/FM radios, HAM and short-wave radios, walky-talkies, baby monitors, and the like.
radar
Microwaves:

Shorter radio waves are called microwaves. Water in microwave ovens responds to these frequencies  by vibrating and heating up.
Radar systems and some communication devices use these frequencies.
Thermogram
Infrared waves

Just below the visible spectrum is infrared light. It is given off by everything that radiates heat. Thermograms can pick up these heat rays, giving us a way to see in the dark using cameras that convert infrared to visible light.
Visible Light
Visible Light

Red, orange, yellow, green, blue, indigo, violet and all shades between. These are the frequencies that our eyes can see.
UV Light
Ultraviolet Rays

High frequency light waves that bees and other insects can see, but humans can not. Skin responds by darkening (tans) and making vitamin D.
Ultraviolet light can kill or mutate cells by breaking DNA and causing mutations.
x-ray
X-Rays

High energy rays that can penetrate soft tissues, leaving white spots on film where they were blocked by bone or other dense things.

Engineers use them to find cracks in metals and cement structures.
Gamma Rays
Gamma Rays

The most energy with the shortest wavelength & highest frequency.

They are the only rays strong enough to escape some stars in large bursts.

Used in medicine to kill tumors using tools like the gamma knife (left)
Karl Jansky
Scientist

Karl G. Jansky (1905-1950) Bell Laboratories Engineer Invented Radio Astronomy when he was looking for sources of static that could interfere with the newly invented radio broadcast systems. He concluded that the biggest source of radiation was coming from the Mily Way galaxy.
ALMA
Technology

Radio Telescopes: The Atacama Large Millimeter/submillimeter Array  "ALMA's test views of the Antennae show us star-forming regions on a level of detail that no other telescope on Earth or in space has attained. This capability can only get much better as ALMA nears completion," said Dr. Mark McKinnon, North American ALMA Project Manager from the NRAO in Charlottesville, Virginia.

B08 Light Waves
Picture Core Knowledge or Concept
ReflectTransmitAbsorb
When light strikes an object, the light can be reflected, transmitted, or absorbed.

Objects can be transparent, translucent, or opaque.
rose

We see most things because of the colors that are absorbed or reflected off of them. The rose reflects red and absorbs blue and green.
Law ofReflection
When a ray of light hits a surface it bounces off at an equal and opposite angle.

Law of reflection states that  the angle of reflection is equal to the angle of incidence.

In regular reflections, parallel rays reflect in parallel, giving a clear image.
In diffuse reflections, rays are scattered,
Focal Length
Optics
The technology of using lenses and mirrors to magnify images by bending light.
A focal point is where light rays meet at a point and an object may come into focus. Its location is given as a distance from the center of a lens or mirror.
Mirror Types
mirror is an object that reflects light.It can be shaped to change the size of an image.It comes in three basic shapes.
  1. plane: flat mirrors produce a reversed image
  2. concave: curved in towards the middle, they have a focal point and can create several different size and position images.
  3. convex: curved outwards from the middle, They create a smaller image 'behind' the mirror.
The curve of a mirror bends light by changing the angle it hits the surface of the mirror.
Refraction
Refraction

Index of refraction: Light travels at different speeds in different mediums. When a wave enters a medium at an angle, one side of the wave changes speed before the other side, causing the wave to bend or refract.

This is how lenses work.  
Types of Lenses
A lens is a shaped object that bends light. In can change the size of an image.  The shape of the lens controls the angle at which the light hits.
Lenses comes in two basic shapes.
  1. concave: curved in towards the middle, they have a focal point behind the lens and can create a smaller image.
  2. convex: curved outwards from the middle, they have a focal point in front of the lens and can create two types of images, upside-down enlarged and .
Eyeglasses and contact lenses focus images on the back of the eye.
Karl Jansky
Scientist

Edwin Hubble (1889-1953 of Wheaton, Illinois) Used observations with light telescopes to confirm the existence of galaxies in an expanding universe..
The Hubble space telescope was named in his honor. It uses a large mirror.
Reflecting Telescope
refracting telescope
Technology

Light Telescopes:

Reflecting telescopes (invented by Sir Isaac Newton ca 1668) use concave mirrors to focus animage into a lens.

Refracting telescopes (first used for astronomy by Galileo Galilei in 1609) use lenses to magnify distant images.The first western telescopes appeared around 1600 in the Netherlands.
B09 Magnetism
Picture Core Knowledge or Concept
lodestone
Magnets are materials that attract iron.
They can be made out of the elements iron, nickel, cobalt (and less often neodymium & samarium)
Lodestones are rocks that contains the mineral magnetite.
Materials with iron are called ferromagnetic.
Poles
Magnetic Poles are the strong ends of a magnet.
They always come in North and South pairs.
Opposites (N+S) attract, Same (S+S or N+N) repel.
The Earth's core is a giant iron magnet making Earth's magnetosphere.
Field Lines Magnetic Field is the area around a magnet
Arrows are drawn from the North pole to the South pole.
Where the lines are densest, the force is strongest, like at the poles.
Combined fields
Combining fields
Filed Lines join together when opposite poles attract.
Field lines push and do not join when similar poles repel.
compass
A compass is a device that points along magnetic field lines towards the north and south poles of a magnet.
electron diagram Magnetic fields are created by electrons spinning in the same direction.
domains
Magnetic domains are areas in which the electrons spin in the same direction. The more electrons are aligned, the stronger the field.

You can make a magnetic domain by rubbing iron with one pole of a magnet to align electrons.
You can mess up a magnetic domain by hitting or heating it.

An electric current in a coiled wire can also align electrons, making an electromagnet
Gilbert
Scientist

William Gilbert (1544-1603) wrote the book (6-volumes) called Die Magnete on electricity and magnetism setting the words used in the field ever-after. He described his own experiments and new ideas about Earth's magnetic field.
motor
Technology

Electric Motors use magnets and electromagnets to turn spinning sharft that can be used to make motion.


B10 Static Electricity
Picture Core Knowledge or Concept
Atomic Charge
Electrons (-) and protons (+) are two particles that have equal and opposite electrical charges.
Most atoms have the same number of protons and electrons, so they have a neutral (no) charge.
Electrons can break free of atoms and move to other objects, leaving a positive charge where the protons remain in place.
opposites attract
Opposite charges attract.



Similar charges repel.
E-Fields
Electric Field is the area around a charged particle where electrical force can be exerted.
Arrows are drawn from the positive charge to the negative charge.
Where the lines are densest, the force is strongest, near the charge.
Combined Fields
Combining fields
Filed Lines join together when opposite charges attract.
Field lines push and do not join when similar charges repel.
lightning
Static electricity is the buildup of charges on an object. Electrons build up in fast moving air and water droplets during a thunderstorm.

Static discharge is the loss of charge. Charges move between two objects until their charges are equal.
Lightning is a huge spark that balances a buildup of electrons in the atmosphere.
static hair
The law of conservation of charge states that charges are neither created nor destroyed.

If an object gives up electrons (hair), another object gains those electrons (the balloon.)  .
electroscope
An electroscope is a device that can be used to detect a static charge. A charge is induced in the light leaves that repel each other and split apart.

This picture shows how to build one with foil and an aluminum can.
friction
Static charges can build up in 3 ways, friction, conduction, and induction.

Charging by friction is the transfer of electrons from one uncharged object to another by rubbing.
conduction
Charging by conduction is the transfer of electrons from a charge object to another by direct contact.
StaticInduction
Charging by induction is movement of electrons to one part of an object that is caused by the electric field of a second object. The electric field around the charged object attracts or repels electrons in the second object.
cell
Electrochemical cells (aka batteries) store chemical energy and change it into the energy of static electric charges.
maxwell
Scientist
 
John Clerk Maxwell (1831-1879) developed our unified theory of electricity and magnetism, thus becoming the father of modern physics.
lion
Technology

Lithium Ion batteries
are the new high-energy technology being developed at places like Argonne National Laboratories in Lemont Illinois for use in electric cars and other vehicles.
B11 Electric Current & Circuits
Picture Core Knowledge or Concept
Current
Electric current is the continuous flow of electrons (note: a spark is not continuous.)
The amount of charges per second is measured in amperes (amps or A).
circuit
An electric circuit is a closed (complete) path that allows current to flow.
An open circuit  (switch is open)  stops the flow of electrons.
Resistance at the Molecular Level A resistor or semiconductor is a material like silicon, germanium, or arsenic (used in computer chips) that lose or use electrical energy, slowing the flow.
device
A device is anything that uses or resists the flow of electrons. Devices include resistors, buzzers, and light bulbs.
They are  represented as resistors in a circuit.
conductor
Conductors are materials that allow electrons (red) to flow like metal wires. A conductor transfers electric charge well, but electric charges do not flow easily through every material.
battery
Source:
Charges in an electric circuit flow because of a difference in electrical potential energy called voltage, measured in volts (V).
You can think of voltage as the amount of force pushing an electric current. A voltage source is a device that creates a potential difference in an electric circuit.
Resistance
Resistance is the measure of how difficult it is for charges to flow through a material. The greater the resistance, the less current there is for a given voltage. The unit of measure of resistance is the ohm (Ω). Resistance can vary with:
  • The material from which the wire is made.
  • Length: Longer wires have more resistance.
  • Diameter: Thinner wires have more resistance
  • Temperature: Higher temp, more resistance.
Ohms
FormulasThe relationship between resistance, voltage, and current is summed up in Ohm’s law. Ohm’s law says that the resistance (R) is equal to the voltage (V) divided by the current (I).
series
If all parts of an electric circuit are connected one after another along one path, the circuit is called a series circuit. In a series circuit, there is only one path for the current to take. Because of this, if one light goes out in a series circuit, the other lights will go out. Adding lights to a series circuit will make other lights in the circuit dimmer.
Parallel
In a parallel circuit, there are several paths (called branches) for current to take. If one light goes out in a parallel circuit, the other lights in the circuit will remain lit because there is still current in the other branches. When branches are added to a parallel circuit, the overall resistance actually decreases because the current has more paths to follow.
multimeter
A multimeter includes each of these functions.   
Circuit Symbols
A circuit diagram shows the sources, conductors, and devices (as resistors) using symbols
Bob & Paul
Scientist
 
Paul and Joseph Galvin, founders of Schaumburg Illinois based Motorola along with son Paul, developed the car radio and the germanium based transistor in 1955.
 
Motorola1955
Technology

The Transistor (1955) was the first mass-produced semiconductor, the forerunner of today's microprocessors at the heart of telephones, TVs, and almost all electronic devices. Transistors allowed early miniaturization of low-power electronics.
The older vacuum tubes used to break,burn out, use alot of electricity, and alot of space.
B12 Electromagnets & Motors
Picture Core Knowledge or Concept
Mag-Current
Whenever electrons flow , they generate a magnetic field that wraps around the direction of the current.

If you move a magnet near a coil of wire, a electrons begin to flow in the circuit.
This relationship is know as electromagnetism.
solenoid
A solenoid is a coil of wire that increases the electromagnetic effect. The ends of the coil become the north and south poles of the magnetic field.
Domains A solenoid's magnetic field has three properties.
  1. The field can be turned on or off.
  2. Reversing the current reverses the north/south poles.
  3. Increasing the current makes the magnetic field stronger.
electromagnet
Adding a ferromagnetic material inside the coil creates an electromagnet.
An electromagnet can be made stronger by:
  1. Adding more coils.
  2. Increasing the current.
  3. Making the coils closer.
  4. Use a stronger ferromagnetic material.
wire moves in field

When a current-carrying wire is placed in a magnetic field, electrical
energy is converted into mechanical energy.
Generator Moving a magnetic field near a solenoid generates an electrical current.
motor gif
An electric motor is a device that uses an electric current to turn an axle. An electric motor converts electrical energy into mechanical energy.
Samuel Morse
Scientist

Samuel Morse (1791-1872) inventor who improved the telegraph and developed a binary communications method (Morse Code) that is the basis of digital communications today (digital computers& media.)
telegraph
Animation
TechnologyDiagram

The telegraph was the 'father' of modern telephones & computers today. It used electro - magnets to communicate 'dots and dashes' over thousands of miles acrossf oceans before wireless radios.