Wt=50N

1. What is the KE at point A? Why?2. What is the PE at point A?3. What is the ME at point A?4. What is the height at point B?5. What is the height at point C?

A.

B.C.

WARM UP

Warm up…

1. What is heat?

2.How does thermal energy play a role in the Law of Conservation of Energy?

Roller Coaster Energy Problems

1. Find the PE at point A.2. Find the KE at point A.3. Find the ME at point A.4. Find the KE at point B.5. What is the ME at point C?6. Find the PE at point C.7. Find the KE at point C.

HT=250 mWT=200N

HT=20 mWT=200NM=20kg

V=200m/s

Answer the problems on the left on your sheet under the

roller coaster picture.

A.

B.C.

Warm up…

1. Describe the energy transfers that occur in a light bulb.

2. Describe the energy transfers that occur when the body is

powered by food.

Warm up…

1.Describe the energy transfers in a hairdryer.

2.What is the difference between renewable and

nonrenewable energy resources?

Types of EnergyForms Explanation Example

MechanicalTotal energy of

motion and position

ThermalTotal kinetic energy

of particles

ChemicalEnergy stored in

rearranging atoms

Types of EnergyElectrical

Energy of moving electrons

SoundEnergy of vibrating

particles

LightVibrations of electrically

charged particles

NuclearEnergy in the nucleus of

an atom

1. Mechanical Energytotal energy of motion and position

ME=KE + PE

2. Electrical Energythe energy of moving electrons

Like charges repel and

Opposite charges attract

++

+ -

The Power of ElectricityCan be turned into other kinds of energyCan do work

Hairdryer converts electric to thermalAlarm clock converts electric to sound and

light

3. Nuclear Energy

Fission Fusion

the energy of the nucleus of an atom

The Sun

Giant nuclear fusion reactor

Ultimate source of energy for our planet

4. Chemical Energythe energy of rearranging atoms

Is photosynthesis endothermic or exothermic?

Is respiration endothermic or exothermic?

5. Sound Energy

-caused by vibrations & carried through a substance.

the energy of vibrating particles

6. Light Energythe vibrations of electrically charged particles

Called PHOTONS

The EM SpectrumVisible light is one portion of

the Electromagnetic Spectrum.

All of these waves are energy-filled waves.

Insects, like bees, see shorter wavelengths than humans. What type of EM waves do they see?

WATCH IT! - prism

Possibilities of LightLight rays move away from their source in straight lines.

When they hit something, they are either

Reflected(bounced off)

Refracted(bent)

Absorbed(stopped)

WATCH IT! - Mirror

Sound & Light: Alike, but Different

Sound*vibration*needs a medium

*longitudinal

Light

*does NOT need a

medium*transverse

Both

are

WAVES

7. Thermal Energy

more thermal energy = faster moving particles

less thermal energy = slower moving particles

the total kinetic energy of the particles

Thermal Energy vs. HeatHeat is the transfer of energy between objects that are at different temperatures.

Three Kinds of HeatConduction Convection

Radiation

(touch) (current) (rays)

Hot Cold

Common