Bell Work

1. Define energy.

2. What is kinetic energy?

3. What is potential energy?4. In order to find weight, you need to know

mass and _________.

*Get out your orange Notes sheet from yesterday.

Forms of Energy

Think-Jot-Share

• How did you get to school today?

• How did that use energy?

Learning Target

• I will explain how an object’s mechanical energy is determined.

• I will distinguish between the different forms of energy.

Mechanical Energy

Mechanical Energy – energy based on the position and motion of an object.

Mechanical energy usually involves moving parts working to create

movementEx: Machines

A thrown ball is affected by kinetic energy and gravitational potential

energy

Mechanical Energy

The bowling ball has mechanical energy.

When the ball strikes the pins, mechanical energy is transferred to the pins!

Examples of Mechanical Energy

Mechanical Energy

Mechanical Energy is a combination of an object’s potential energy and its kinetic energy.

Ex. See football example pg.170ME = 32J + 45J ME = 77J

Mechanical Energy = Potential energy + Kinetic energy(position) (motion)

Mechanical Energy Practice

If an object has 50 joules of kinetic energy and 237 joules of potential energy, what is its mechanical energy?

237J + 50J =

Mechanical Energy = Potential energy + Kinetic energy

287J

Thermal Energy

• Thermal energy – the total amount of potential and kinetic energy of the particles (atoms & molecules) in an object.

o A hot object has atoms and molecules that are excited and show rapid movement.

o A cooler object's molecules and atoms will show less movement.

Electrical Energy

• Electrical Energy – energy caused by the movement of electrons

– Ex. When you get shocked from touching the doorknob.

• May be kinetic or potential energy

Chemical Energy

Chemical Energy - the energy released by the breaking of chemical bonds.

Eating food breaks the chemical bonds within it for consumers to use as

energy.

Chemical energy can also of the energy in the

form of heat being released.

Chemical Energy

The chemical bonds in a matchstick store energy that is transformed into thermal energy when the match is struck.

Chemical Energy in Food

• Chemical energy that is stored in food can be measured in kilocalories (known as calories).

• When you look at a food label, what does the number of calories per serving indicate?– The amount of stored energy in one serving of the

food.

Nuclear Energy

• Nuclear Energy - Energy stored in the nucleus of an atom is released during a nuclear reaction.

• Ex. Nuclear fusion & nuclear fission

Electromagnetic Energy

• Electromagnetic energy – light energy that travels in waves

• Some have electric properties & some have magnetic properties.– Ex. Visible light, X-rays, ultraviolet radiation,

infrared radiation, gamma rays, microwaves, & radio waves

QUIZ TIME!What type of energy cooks food in a microwave oven?

ELECTROMAGNETIC ENERGY

What type of energy is the spinning plate inside of a microwave oven?

MECHANICAL ENERGY

What type of energy is shown below?

Chemical Energy

What types of energy are shown below?

Electrical, Mechanical, andElectromagnetic Energy

What type of energy is shown below?

Chemical Energy

What type of energy is shown below?

Thermal Energy

What types of energy are shown below?

Mechanical and Thermal Energy

Practice

• Do the practice problems on your notes sheet.

Assignment

• Complete the questions on pg. 173– #1, #2, & Writing in Science