SI Units (Metric)

Quantity Name Symbol of Unit

meter m length centimeter cm

kilometer km

kilogram kg mass gram g

milligram mg

second s time minute min

hour hr

force Newtons N

temperature Kelvin °K

Metric Conversion

King Henry Died By Drinking

Chocolate Milk!

Conversion Factors

Factor US Unit Multiply by:

Equals METRIC unit

Length Inches 2.54 Centimeters (cm)

Feet .3048 Meters (m)

Miles 1.61 Kilometers (km)

Weight Ounces 28.35 Grams (g)

Pounds .45 Kilograms (kg)

Volume Fluid Ounces

29.57 Milliliters (mL)

Gallons 3.79 Liters (L)

Temperature Fahrenheit (0F-32) X 5/9

Celsius (0C)

Factor Metric Unit Multiply by:

Equals US unit

Length Meters 3.28 Feet

Kilometers .62 Miles

Weight Grams .035 ounces

Volume Liters 4.23 cups

Liters .26 gallons

Temperature Celsius (0CX1.8)+ 32

Fahrenheit

Factor Equation Equals Metric Unit

Temperature 0C+273 Kelvin (K)

K-273 Celsius (0C)

Scientific Method/ Experimental Design/

PHEOC

Step 1: Ask a question or have a purpose for

investigation.

Step 2: Develop a Hypothesis (3rd

person). Try NOT to

use an If…Then statement. Additionally, your

hypothesis needs to be TESTABLE!

Quantity Name Symbol

of Unit

meters 2 m 2

area centimeters 2 cm 2

millimeters 2 mm 2

meters 3 m 3

volume centimeters 3 cm3

millimeters 3 mm 3

- kg/m3

density - kg/cm3

- g/cm3

2013 AC Science Cheat Sheet

Step 3: Research, Write detailed and PRECISE

procedures, identify your variables and control(s), and

conduct your experiment. Don’t forget that valuable

experiments usually consist of multiple trials. Remember

the following terms:

o Independent Variable: (AKA

Manipulated Variable): this is what you

change in an experiment…what you

manipulate.

o Dependent Variable: these are your

observations based upon what you

changed in your experiment. Your

dependent variable DEPENDS on your

independent variable(s).

o Control: your point of reference in an

experiment. This would be something

that is not manipulated.

o Accurate: exactness of a measurement

o Precision: repeatable with the SAME

results

o Reliable: trustworthy research

o Valid: based on facts

Step 4: Record ALL Data (Quantitative (number data)

and Qualitative (quality/characteristic data)) and

Observations.

Step 5: Analyze your data and construct a well-

developed Conclusion (in 3rd

person).

Theory: a testable idea for an unexplained phenomenon.

Law: states a fact, but does not explain why.

Tools

Mass = triple-beam balance or digital scale

Weight/Mass = Spring Scale or digital scale

Temperature = thermometer

Volume of regular solid = metric ruler/meter stick

Volume of irregular solid or liquids = beaker and

graduated cylinder

Heating liquids = Erlenmeyer flask and tongs.

Formulas in Physical Science

Speed = distance (D)/time(T)

o Measured in meters/hour (base unit)

(m/hr) or (m/s)

Average Speed = total distance/total time

o Measured in meters/second (base unit)

(m/s)

Acceleration = force (F)/mass (m)

o Unit = meters/second (m/s)

Force = mass (m) X acceleration (a)

o Unit = newton (N)

Mass = force (F) X acceleration (a)

o Unit = grams (g)

Average Acceleration = final velocity-starting

velocity ÷ time it takes to change velocity

o Unit = meters/second2 (m/s

2)

Net Force…

o Traveling in the same direction = ADD

o Traveling in opposite direction = subtract

o Unit = newtons(N)

Work = Force(F) X Distance(D)

o Unit = Newton/Meter AKA a JOULE (J)

Power = Work(J) ÷ Time(T)

o Unit = Watt (W)

Pressure = Force (F) ÷ Area(A)

o Unit = Pascal (Pa)

Density = Mass(m)÷ Volume(V) o Unit = g/cm

3

Concentration = mass of solute ÷ volume of

solvent

o Unit = g/mL

Velocity of a Falling Object = Δv(change in

velocity) = gravity constant (g = 9.8m/s2) X

Time(T)

o Δv = g X t

o Unit = m/s

Rearrange to find time…

o T = Δv ÷ g

o Unit = seconds (s)

Volume of a REGULAR object = V (volume) =

length X width X height o Unit = cm

3

Volume of an IRREGULAR object…use

DISPLACEMENT METHOD (graduated cylinder

with water). The change or displacement of

water is your volume.

o Unit = mL (1mL = 1cm3)

How many Electrons will fit in each energy

level?

o 2(N2) N=the energy level number

Momentum…

o P(Momentum) = Mass(m) X Volume(v)

o Unit = kg*m/s (include a

direction…N,S,E,W)

Mechanical Advantage (MA)= output force ÷

input force

o Unit = Newton (N)

Mechanical Efficiency = work output ÷ work input

X 100

o Unit = percentage

Kinetic Energy(KE) = mass(m) X volume2 (v

2) ÷

2

o Unit = Joules (J)

Gravitational Potential Energy (GPE) = weight

(N) X height (m)

o Unit = Joule (J)

Mechanical Energy (ME) = Potential energy (PE)

+ Kinetic energy (KE)

o Unit = Joule(J)

Ohm’s Law

Resistance (R) = Voltage (V) ÷ current (I)

o Unit = Ohm (Ω)

OR

Voltage (V) = Current(I) X Resistance (R)

o Unit = Volts (V)

Electric Power = Voltage (V) X Current (I)

o Unit = Watt (W)

Electrical Energy = Power (P) X Time(T)

o Unit = Kilowatt hours (kWh)

Wave Speed (v) = Wavelength (λ – Greek letter

lambda) X Frequency (f)

o Frequency’s unit is Hertz(Hz)

o Unit for Wave speed = m/s

Can Rearrange the formula…

Wavelength (λ) = wave speed (v) ÷ Frequency

(f)

Frequency (f) = wave speed (v) ÷ Wavelength

(λ)

Mass vs. Weight

Mass is the amount of matter in an object, measured in

grams by using a triple-beam balance or digital scale.

Mass is CONSTANT and does NOT change based on

your location in the universe.

Weight is a factor of gravitational force measured in

Newtons by using a digital scale or spring scale. Weight

FLUCTUATES based on your location in the universe.

Laws in Physical Science

Law of Conservation of Mass/Matter: states matter

cannot be created or destroyed during a chemical or

physical change

Law of Conservation of Energy: states energy cannot be

created or destroyed

Universal Law of Gravitation: states all objects are

attracted to each other due to gravity.

o Part 1: The larger the mass, the greater

the gravitational pull and vice versa.

o Part 2: The greater the distance, the

lesser the gravitational pull and vice

versa.

Newton’s First Law of Motion: states an object in motion

stays in motion until acted upon by an unbalanced force.

Example: bumper cars and FRICTION!

Newton’s 2nd

Law of Motion: (sometimes called the Law

of Inertia) states the acceleration of an object depends

on the mass of the object and the force applied.

Example: compare pushing an empty grocery cart to a

FULL grocery cart.

Can be expressed as an equation: F=m

X a or a= F ÷ m

Newton’s 3rd

Law of Motion: states for every action,

there is an equal and opposite reaction. Example:

kicking off a wall in a swimming pool.

Law of Reflection: states that the angel of incidence is

equal to the angle of reflection. Light reflects off a

surface at the same angle that light strikes the surface.

Charles’ Law: states that for a fixed amount of gas at a

constant PRESSURE, the volume of the gas increases

as the temperature increases and vice versa. Example:

Mylar balloons shrinking in cold weather and swelling in

hot weather.

Boyle’s Law: states that for a fixed amount of gas at a

constant TEMPERATURE, the volume of a gas

increases as the pressure increases (inversely

proportionate) and vice versa. Example: Blowing

bubbles at the bottom of the pool…the bubbles increase

in size as they rise to the top of the water.

Law of Momentum: states that any time 2 objects collide,

the total amount of momentum remains the same.

Chemistry Cheats

Examples of Chemical Properties

Examples of Physical Properties

Reactivity with Oxygen Thermal Conductivity

Flammability State

Reactivity Density

Solubility

Ductility

Malleability

Examples of Chemical Changes

Examples of Physical Changes

Soured Milk Change in state

Effervescent tablets Slicing

Rusting Tearing

Tarnishing Mashing

Forming of a gas Dissolving

*Changes the Composition*

*NO change in composition*

*Not easily reversed* *May be reversed*

The 5 States of Matter

Solids have particles that are tightly packed and

VIBRATE in place.

Liquids have particles that are just far enough to SLIP

PAST each other.

Gases are particles that are WIDELY SPREAD.

Plasmas are gas particles that carry an ionic (electric +

or -) charge. Only occurs on Earth as lightning.

Bose-Einstein Condensate (BEC) occurs as an atom

(like rubidium) condenses hence its name. BEC’s were

discovered in 1995, but predicted in the 1920’s by Bose

and Einstein. Think of the BEC like an atomic “blob.” As

an atom approaches Absolute Zero (the point where all

matter stops moving), the particles in the atom clump up

and form a “blob-like” substance.

Changes in State

Changes in state are simply caused by the adding and

removing of energy. See the table below.

Adding Energy = Endothermic

Removing Energy = Exothermic

Periodic Table

Vertical columns on the Periodic Table are called

GROUPS or FAMILIES and share common

characteristics.

Horizontal rows on the Periodic Table are called

PERIODS. Elements chance “periodically” as you move

from left to right across the table. The pattern occurs

every 7 elements.

The Lanthanides and Actinides (so called because they

begin with the elements Lanthanum and Actinium) are

the 2 bottom rows that are pulled out separate at the

bottom of the table. This is simply to make the table

more user friendly. They are not “special.”

Atomic Theory

Date Scientist Credits Democritus 440 BCE Naming the atom, a

particle that cannot be cut

Aristotle 322 BCE Particles could be infinitely (he was wrong)

Dalton 1803 Developed Atomic Theory: all substances made of atoms, cannot be created/divided/destroyed, join to make new substances. (Almost right!)

Thomson 1897 Plum Pudding Theory…Electrons were the “plums”; Cathode Ray Tube

Rutherford 1909 “shooting gallery”; named the nucleus and claimed it was positively charged (protons)

Bohr 1913 Atomic structure – electrons orbit positively charged nucleus.

Shrodinger and Heisenberg

Later 20th

Century

Modern Atomic Theory…electrons spin randomly around the positively charged nucleus in electron clouds.

Three Kinds of Elements on the Periodic Table

Metals are found on the left of the zigzag line on the

table. Metals are solid at room temperature, typically

shiny, malleable, ductile, and good conductors.

Nonmetals are found to the right of the zigzag line on the

table. Nonmetals are typically gases at room

temperature. They are not shiny, malleable, or ductile.

Nonmetals are not good conductors.

Metalloids are also called semiconductors. They are

found along the zigzag line on the table. Metalloids have

properties of both metals and nonmetals. Metalloids are

responsible for many of our technological devices we

use.

Sample Element from the Periodic Table

There are 3 types of particles found in an atom:

Protons are POSITIVE and located in the nucleus.

Protons are medium-sized in relation to mass.

Neutrons are NEUTRAL are located in the nucleus

tightly packed with the Protons. Neutrons are the

HEAVIEST particles and are responsible for the MOST

of the mass of an atom.

Electrons are NEGATIVE are found in the ENERGY

LEVELS/ ELECTRON CLOUDS/ ORBITS that circle the

nucleus. Electrons are insignificant in mass (VERY

small).

Atomic Structure

Symbol

Name of

Element

Atomic Number

Atomic

Mass

Valence

Electrons

Energy Level #1

Energy Level #2

The Number of Protons and Electrons = the Atomic

Number (in a NEUTRAL atom…NOT an ion!)

The Number of Neutrons can be found by taking the

difference between the Atomic Mass (rounded to the

nearest whole number) and the Atomic Number.

Atomic Mass can be found by adding Protons and

Neutrons. Atomic Mass is measured in Atomic Mass

Units (AMU’s) and is an average of naturally occurring

elements, hence the decimals.

Valence Electrons are the “hook up” electrons and

define an elements ability to bond with other elements to

form molecules and compounds. The “magic numbers”

for Valence Electrons and bonding are 2 (for the lowest

numbers on the table) and 8 for the rest of the table.

Building with Atoms

An ATOM is the smallest unit of an element that can still

be identified to have qualities of the element.

An ELEMENT is a substance that CANNOT be broken

down into a more simplistic substance by ANY chemical

means.

A MOLECULE is a chemical combination of any 2 or

more ATOMS. Example: O2 OR H2O

A COMPOUND is a chemical combination of any 2 or

more ELEMENTS (has a symbol on the Periodic Table).

Example: H2O

**ALL compounds are molecules, but NOT all molecules

are compounds. Example: O2**

IONS are POSITIVELY or NEGATIVELY charged

elements.

ISOTOPES are different versions of the same element

that have varying atomic masses and number of

neutrons.

Mixture – combination of substances that are NOT

chemically combined – Example: a tossed salad

Suspension – mixture where the particles settle out –

Example: Italian salad dressing

Solution – mixture where a solute is dissolved into a

solvent, but can be separated. Example: salt water

Solute – the particle that is dissolved in a solvent.

Example: salt

Solvent – the particles into which a solute is dissolved.

Example: The UNIVERSAL SOLVENT – WATER!

Colloid – mixture where solid particles separate.

Example: Jello or Milk

Chemical Equations

Prefixes for Writing Chemical Equations

Number of Atoms Prefix

1 Mono

2 Di

3 Tri

4 Tetra

5 Penta

6 Hexa

7 Hepta

8 Octa

9 Nona

10 Deca

Bonding: 3 types

Ionic – the gaining or losing of ELECTRONS. Results is

a positive or negatively charged atom. If electrons are

LOST, the atom is POSITIVE. If electrons are GAINED,

the atom is negative. Normally occurs between a metal

and a nonmetal.

Covalent – the sharing of electrons. Usually a nonmetal

and another nonmetal.

Metallic – bonding between 2 or more metals. Can be

ionic or covalent.

Counting Atoms

H2O – has 3 atoms (2 H and 1 O)

2H2O – has 6 atoms (4 H and 2 O) – you simply

distribute the Coefficient throughout the compound.

YIELDS

SUBSCRIPTS…NO

TOUCHY!!

Balancing Equations

Here is a website for you to practice with!

http://richardbowles.tripod.com/chemistry/balance.htm#p

art1

Types of Chemical Reactions

Acids and Bases

ACIDS are compounds that increase the number of

hydronium (positive) ions when dissolved in water. Acids

tend to be sour and corrosive. Acids turn litmus paper

RED!

BASES are any compounds that increase the number of

hydroxide (negative) ions when dissolved in water.

Bases are typically bitter and slippery. Bases turn litmus

paper BLUE!

pH Scale

Physics Cheats

Speed Graph

VELOCITY is SPEED with a DIRECTION!

ACCELERATION is ANY change in VELOCITY, so ANY

change in SPEED OR DIRECTION. Acceleration can be

positive or negative (deceleration). The faster the

velocity changes, the greater the acceleration.

Continuous Acceleration is achievable by circular motion

or Centripetal Acceleration. The object is CONSTANTLY

changing direction while traveling in a circle.

Acceleration Graph

Force

A FORCE is any push or pull.

Forces can be calculated. NET FORCE is the total of

ALL forces acting on an object, measured in Newtons.

Forces acting in the SAME direction are ADDED

together.

Take the DIFFERENCT between forces acting in

OPPOSITE directions.

BALANCED FORCES occur when net force equals

ZERO. This occurs when an object is NOT moving OR

moving at a CONSTANT VELOCITY (no speed or

direction changes).

UNBALANCED FORCES occur when an object is in

motion. Unbalanced forces CAUSE changes in motion.

FRICTION is a force that opposes motion. Friction is

EVERYWHERE! There are 2 kinds: Kinetic (friction in

motion) and Static (object is not moving).

GRAVITY is a force of attraction between objects due to

their masses. ALL objects are subject to gravity! Gravity

is a result of mass! We must overcome gravity to move!

Synthesis

Decomposition

Single

Displacement

Double

Displacement

ALL objects accelerate towards the Earth at the SAME

rate. That rate is 9.8m/s2. The variances we see in

objects falling at different rates is caused by FRICTION!!

Air Resistance = FRICTION!!

TERMINAL VELOCITY is the point at which a falling

object ceases to accelerate and falls at a CONSTANT

rate.

FREE FALL is ONLY possible when an object is

weightless, therefore FREE FALL is ONLY possible in

space or when an object is in ORBIT. Orbiting has 2

motions…forward and down (free fall).

Projectile motion is a combination of 2

motions…horizontal THEN vertical (forward THEN

down). This allows us to see the curved path that an

object creates as it is thrown.

INERTIA is the tendency of an object to resist a change

in motion. INERTIA holds you in your seat on an inverted

roller coaster. The GREATER the MASS, the GREATER

the INERTIA!

Work

WORK is done when a force causes an object to move

in the SAME direction as the force.

Kinetic Energy = energy in motion

Potential Energy = energy of position

POWER is the rate at which WORK is transferred.

Simple Machines

MACHINES make work easier by changing the SIZE or

DIRECTION of a force.

WORK INPUT = work done on a machine (what you put

in)

WORK OUTPUT = work done BY the machine

PERFECT Machines (100% Efficiency) are NOT

possible due to the existence of FRICTION!!

Levers

LOAD = what you are moving

FULCRUM = fixed point where a pivot occurs

Pulleys

Fixed Pulley (Elevator) Movable Pulley (Distance)

Block and Tackle Pulley (share the load)

First

Class

Second

Class

Third

Class

Wheel and Axle

Wheel is larger than the axle, so

the output is greater than the input.

Inclined Plane

Increase distance, but decrease

input force.

Wedge

Pair of inclined planes that move.

Output force is greater than the input.

Distance is increased.

Screw

Small force applied over a long

distance and vice versa. A type of

inclined plane.

COMPOUND MACHINES are any combination of SIMPLE

MACHINES!

Heat Transfer: 3 types

Temperature: measure of the average kinetic energy of the

particles in an object (technically there is NOT hot or cold!)

Radiation: transfer in waves – heat you can feel

Conduction: transfer by direct contact – touching a hot pot

Convection: heat transfer through a fluid (liquid or gas) in a

circular pattern – like water boiling in a pot

Temperature Scale Comparison

Fission and Fusion

FUSION: Nuclei join together to form a larger nuclei.

This is what happens with our Sun!

FISSION: Large nuclei splits and forms 2 new nuclei.

HALF-LIFE: the time it takes for HALF of a given sample to

decay so it is no longer detectable.

Energy Conversion

Energy Conversion: changing of energy from one form to

another. Energy is never created or destroyed, but can be

transferred. Thermal Energy (heat) is ALWAYS part of an

energy conversion.

Conductors and Insulators

Conductors Insulators Curling iron Flannel shirt

Cookie sheet Oven sheet

Iron skillet Plastic spatula

Copper pipe Fiberglass insulation

Stove coil Ceramic bowl

Waves, Light, and Sound

Waves – any disturbance that transmits itself through matter

or empty space

Medium – substance through which a cave can travel (solid,

liquid, or gas)

2 kinds of waves:

Transverse: looks like a rope being moved;

contains crests (the high point of the wave) and

troughs (the lowest point of the wave). Water

waves are transverse waves.

Longitudinal: looks like a slinky or spring;

contains compressions (areas where the coils are

tightly pressed together) and rarefactions (areas

where the coils are spread apart). Sound is a

longitudinal wave.

Surface Waves – combination of both types, like an ocean

wave

Wavelength – distance from crest to crest or trough to

trough, measured the same in both types of waves.

Wavelength can be calculated by

multiplying wave speed times frequency; measured

in meters

More energy = shorter wavelength

Less energy = longer wavelength

Amplitude – height of a wave from a rest position - can be

measured from rest position to the top of the crest or rest

position to bottom of trough

Frequency – number of waves produced in a given amount of

time

Calculated by dividing wave speed by

wavelength, measured in Hertz (Hz)

Higher frequency = more energy

Lower frequency = less energy

High and Low Frequency

Wave Speed –

speed at which a

wave travels

Calculated by multiplying wavelength times

frequency, measured in meters per second

Frequency and Wavelength – as frequency increases,

wavelength decreases – they are inversely proportionate

Reflection – wave bounces back after hitting a barrier – echo

is a sound wave reflecting

Transmitted – when waves pass through a substance

Refraction – bending of a wave as the wave goes from one

medium to another at an angle – this is how we see a

rainbow using a prism or after a rain shower. This is caused

by the wave changing speed as it changes medium.

Diffraction – bending of waves around a barriers or through

an opening – this why you can hear music before you can see

it

Waves are energy, therefore they can be in the same place

at the same time (unlike physical objects)…waves can meet,

travel thru each other, and keep going (overlapping)

Interference - When waves overlap

Constructive interference – crests or troughs

overlap…energy is combined…new wave has higher crests

and deeper troughs – larger amplitude.

Destructive interference – crest from one & trough

from another overlap…smaller amplitude – possibly destroy

wave.

Standing Wave – caused by loops of interference…looks like

wave is not moving – formed from transverse waves (like a

guitar string) and longitudinal waves.

Frequency at which standing waves are made are called

resonant frequencies.

Resonance – object vibrates and causes another object to

vibrate (mirror with bass sound, drums, singing in shower,

xylophone, etc.)

Sound waves are longitudinal and MUST have a medium to

travel. Sound travels by creating vibrations. Therefore, the

more tightly packed the particles are – the faster the sound

wave can travel. So, sound travels fastest in solids, followed

by liquids, and lastly the slowest in gases. Temperature also

affects the speed of sound. The cooler the medium, the

slower the sound.

The ear – sound enters through the outer ear, is amplified by

the middle ear (with the bones: hammer, anvil and stirrup),

and lastly changed into electrical signals to be sent to the

brain in the inner ear.

Speed of sound – Chuck Yeager was the first person to fly a

jet faster than the speed of sound. When an object

approaches the speed of sound, gases begin behaving more

like a fluid. When the objects reaches the speed of sound and

then begins to move faster it is called breaking the sound

barrier. This act results in what is called a sonic boom. The air

particles are moving and colliding so quickly that it generates a very

loud sound.

Speed Variances Based on State

Sounds travel fastest through solids, then liquid, and gases

are the slowest!

Pitch – How low or high a sound seems – pitch is related to

frequency, the higher the pitch – the higher the frequency.

Doppler Effect – apparent change in frequency of a sound

caused by the motion of the listener or the source of the

sound. Like hearing an ambulance, fire truck, or police car’s

siren.

Loudness – measure of how well a sound can be heard – air

particles are moving faster in a loud sound. Loudness is

measured in decibels (dB) Average humans can hear a low as

0 dB. Sounds higher than 120 dB are painful.

Amplitude – the height of a wave from the rest period. When

you apply for force to increase loudness, you increase the

height of the wave. Therefore loudness and amplitude are

related.

You can see the relationship between frequency and

amplitude by using an oscilloscope. It takes longitudinal

sound waves and creates a transverse wave, so you can “see

the sound.”

Electromagnetic Spectrum

Electromagnetic spectrum (EM Spectrum): diagram of ALL

frequencies based on WAVELENGTH of electromagnetic

radiation!

Radio waves have LONGEST wavelength and LOWEST

frequency…Gamma Waves have the SHORTEST wavelength

and HIGHEST frequency!

Electromagnetism

Law of Electric Charges – like charges repel and opposite

charges attract

Electric Force – force between 2 charged objects

Electric Field – region surrounding a charged object where an

electric force continues to exert on another object

Friction – electrons are wiped from one surface to another

(rubbing a balloon on your head)

Conduction – electrons are transferred by direct contact

(when you are shocked)

Induction – uncharged object is affected without direct

contact (your hair sticking out after you brush it)

Electroscope – allows you to detect charges

Conductors – charges flow easily

Insulators – charges do not flow easily

Static electricity – electric charge at rest on an object

Electric discharge – charges move off of an object (shocking

yourself on a doorknob or lightning)

Electric Current – rate at which charges pass a given point

A/C – Alternating Current: charges flow in both directions

(anything that plugs in)

D/C – Direct Current: charges only flow in one direction

(anything that takes a battery)

Electric Field

Electric Force

Voltage – potential difference between 2 points on a circuit;

measured in Volts (V)

Resistance – “electrical friction” the opposition to flow of a

charge; measured in Ohms (Ω)

Ohm’s Law – states that there is a direct correlation between

resistance and voltage for individual elements. Poor

conductors have a high resistance; Good conductors have low

resistance

Formula: Resistance(R) = Voltage (V) divided by

Current (I)

Expressed in Ohms (Ω)

You can rewrite the formula to find Voltage by

multiplying Current times Resistance

Best wires: short, fat, and cool

Resistance increases based on thickness of wires, length of

wires, and temperature of the material.

Cells – changes chemical or radiant energy into electrical

energy

Electrolyte: mixture of chemicals that allows charges

to flow

Wet Cell: have liquid electrolytes (a liquid can

complete the circuit)

Dry Cell: have solid electrolytes

Thermocouple: converts thermal energy to electrical energy

Photocells: converts light energy to electrical energy (solar

calculator)

Electric Power: rate at which electrical energy is converted to

other types of energy

Circuit: a closed path that forms a loop

Switch: can be used for safety reasons to control a circuit

A circuit MUST be CLOSED in order for the charge to flow!

Series Circuit – all parts are connected in s single loop – when

one light goes out – they all go out. Only one way in and one

way out (old Christmas tree lights)…bulbs burn equally bright,

but get dimmer as you add more – this is because the charge

has further to flow – you are increasing the resistance

Parallel Circuits – all parts are connected side-by-side – when

one light goes out – the charge can bypass and move to the

next light. All bulbs receive the maximum amount of charge;

therefore they always burn their brightest. This is why you

can plug in your hair dryer, radio, and phone charger in at the

same time!

Circuit Safety – all buildings/constructions are made with an

“electrical hub” or a fuse box/circuit box/breaker box. These

boxes control the charges flowing through the building. Inside

the boxes are switches controlled by FUSES. Fuses expand

and contract as charges flow through the box. If the fuse

detects too much charge flowing it will expand and close the

switch connected to that part of the building – therefore

shutting off all power to the area for safety reasons. You may

have experienced this is your home by having too many

things plugged in.

Magnets

Magnets – any material that attracts iron or things made

from iron

All magnets have 2 poles – north and south

Like poles repel, while opposite poles attract

Magnetic Force – spinning electric

charges in a magnet generate this

force

Magnetic Field – region that

surrounds a magnet where the

forces act

Ferromagnetic Material – objects made from iron, nickel, or

cobalt

Domains – areas inside the magnet that hold groups of

atoms.

When domains line up – the magnet is magnetized. When the

domains are knocked out of alignment or disrupted – the

magnet is no longer magnetized (demagnetized).

Creating Magnets – you can create a magnet by rubbing a

ferromagnetic material on a magnet. This creates relatively

weak and temporary magnets only.

Cutting a magnet – when you cut or break a magnet you end

up with 2 new magnets. Whatever end breaks off (North or

South) will regenerate after the domains realign and you will

now have 2 magnets instead of 1.

Destroying magnets – magnets can be destroyed by heating,

hitting the magnet with a dense object, or striking an object

with the magnet. Anything that causes the domains to be

knocked out of alignment will destroy a magnet.

Don’t forget the Earth is like a giant bar magnet. This is

proven by using magnetic compasses that point to magnetic

north.

Electromagnetism – an interaction between electricity and

magnetism

Electromagnet Diagram

AN ELECTRIC CURRENT CAN GENERATE A MAGNETIC FIELD!!

Creating electromagnets – you can take a piece of

ferromagnetic material and wrap a piece of copper wire

around it creating a coil. This coil is called a SOLENOID. If you

attach the wires on each end to an electrical device (like a

battery); you have created an electromagnetic! If you want

to increase or decrease the power of the electromagnetic,

simply increase or decrease the number of coils of the

solenoid or you may choose to use a stronger ferromagnetic

material.

Electric Motors – changes electrical to mechanical; contains

an armature (loop or coil that can rotate). If the motor uses a

direct current, it may also have a commutator which reduces

the current

Galvanometer – device that measures current

Solenoid

Hans Christian Oersted discovered that electric currents can

produce magnetic fields.

Michael Faraday – tried to prove that an electromagnet could

induce (create) and electric current – he failed. However, he

did find that an electric current could be created by the

process of electromagnetic induction (creating a current by

changing a magnetic field).

Electric generator – uses electromagnetic induction to change

mechanical energy into electrical energy

Transformers – device that increases or decreases the voltage

of an alternation current