ENERGY AND ITS FORMS

Ch 15.1

True False Statement True False

Kinetic energy is moving energy, while potential energy is stored

PE = ½ mv2

KE = mgh

Bouncing a ball is an example of kinetic mechanical energy

Fission and fusion is an example of electromagnetic energy

Potential energy ahs 2 forms: gravitational and elastic

Energy and Work Work is done when

a force moves an object a distance

Work is a transfer of energy

Energy is the ability to do work

Both measured in J

Kinetic Energy Energy of motion

Depends on mass and speed

KE = ½ mv2

SI Units: KE- m- v-

KE Practice A 0.10 kg bird is

flying at a constant speed of 8 m/s. What is the birds kinetic energy?

Given:

Formula:

Solve:

Math Practice pg 448 1.

2.

3.

4.

Potential Energy Energy that is stored due to position or

shape

Stored energy turns into KE

Potential EnergyGravitational PE Elastic PE PE that depends upon an

objects height Increases with increased

height

PE = mgh

SI Unit m- g- h-

PE that is stretched or compressed

Object springs back to its original shape

Forms of EnergyMechanical Thermal Energy associated with

motion and position of everyday objects

Sum of PE and KE

Total PE and KE of all the microscopic particles in an object

Particles move faster, becoming warmer

Forms of EnergyChemical Electrical Energy stored in

chemical bonds Energy associated with

electric charges

Forms of EnergyElectromagnetic Nuclear

Form of energy that travels through space in the form of waves

Energy stored in the atomic nucleus Fission- releases energy,

splits apart Fusion- releases energy,

comes together

ENERGY CONVERSION AND

CONSERVATION

15.2

True False Statement True False

Energy can not be converted into another form

Energy cannot be created or destroyed

To calculate conversions:KE = PE

Einstein said E = mc2, where energy = mass x conservation2

Potential energy turns into kinetic energy

Conservation of Energy Energy cannot be created or destroyed

It is transferred or converted

Energy Conversion Energy can be converted from 1 form to

another Process of changing energy – energy

conversion

Gravitational PE converts into KE as an object falls

Energy Conversions Pendulums

PE constantly converted back and forth to KE

Stays in motion due to weight

Pole Vaults

Energy Conversion Calculations KE + PE = KE + PE (Beginning) (End)

KE=

PE=

Conversion Practice A 1.50kg brick is

dropped from rest and hits the ground at a speed of 26m/s. Ignore air resistance, calculate PE before the brick was dropped.

Given:

Formula:

Solve:

Math Practice pg 458 1.

2.

3.

Energy and Mass Albert Einstein

Theory of RelativityE = mc2

Energy and mass are equivalent and can be converted into each other

c= speed of light 3.0 x 108 m/s

ENERGY RESOURCES

Ch 15.3

True False Statement True False

Nonrenewable resources take millions of years to be replaced

Renewable resources originate directly or indirectly from the sun

Hydroelectric energy is from water deep below the earths crust

Solar energy converts sunlight into useable energy

Biomass energy is from living things and can be converted into

thermal energy

Nonrenewable Energy Exists in limited quantities Once used, it can’t be replaced except

over the course of millions of yearsNatural GasCoalUranium

Also known as fossil fuels

Renewable Energy Can be replaced in relativity short

periods of time

Renewable Energy Hydroelectric

Energy from flowing water

SolarSunlight converted

into useable energy

Renewable Energy Geothermal

Thermal energy beneath Earths surface

OthersBiomass Energy

○ Energy stored in living things

Hydrogen Fuel○ Creates electricity by

reacting hydrogen and oxygen

Conserving Energy Resources Reduce energy needs Increase the efficiency of energy use