Energy:

Before starting this unit, read the following statements and

1.  Write “A” if you agree

2.  Write “D” if you disagree

Agree/ Disagree / Energy
The total amount of energy in the universe never changes.
Any two objects on the same shelf of a cupboard have the same potential energy
Energy is lost when an object is motionless
A light bulb transforms electrical energy into light and thermal energy.

Which takes more energy: Walking up stairs or taking an escalator? Explain your reasoning.

______

______

______

______

______

Scan your book, or look up in the internet at least 4 different forms of energy:

1.  ______2. ______

3. ______4. ______

Read the definitions below, and try to find the appropriate term that goes with it:

1.  ______The energy of a moving object has because of its motion.

2.  ______The SI unit of energy.

3.  ______Stored energy due to position.

4.  ______Energy stored by something that can stretch or compress.

5.  ______Energy stored in chemical bonds.

6.  ______Energy stored by objects due to their position above Earth’s surface.

Kinetic Energy:

Complete the formula for the kinetic energy equation of a moving object. Use mass (kg), speed (m/s), and Kinetic Energy (joules) in your equation.

Work Equation:

______= 12 ______X [______]2

Symbol Equation:

Potential Energy:

Complete the formula for the Potential Energy equation of an object a certain height. Use weight (N), height (m), and Potential Energy (PE)

Word Equation:

______= ______X ______

Symbolic Equation:

Analyze the types of potential energy being used by an athlete competing in each of these athletic events.

Archery: ______

Sprinting: ______

Platform Diving: ______

Complete the concept map by entering each term or phrase in the appropriate location.

Chemical energy gravitational

mgh potential energy ½ mass X velocity2

Define the following terms:

Friction: ______

Mechanical Energy: ______

Law of Conservation of Energy: ______

Sequence the four energy transformations, such as those related to fossil fuels.

1.  ______

2.  ______

3.  ______

4.  ______

To the right, create a drawing of an apple falling from a tree. Label where:

·  Kinetic energy is low and gravitational potential energy is high.

·  Kinetic energy is high and gravitational potential energy is low.

·  Kinetic energy is about equal to gravitational potential energy.

Energy Wrap-Up:

Write an “A” if you agree with the statement. Write a “D” if you disagree with the statement.

Energy / Agree or Disagree
The total amount of energy in the universe never changes.
Any two objects on the same shelf of a cupboard have the same potential energy.
Energy is lost when an object is motionless
A light bulb transforms electrical energy into light and thermal energy

Self-Check Quiz:

_____ 1)  A book sits on a desk that is 1 meter (m) high. The book’s gravitational potential energy is 10 joules (J). If the book falls from the desk, what is the sum, in joules, of its gravitational potential energy and kinetic energy when the book is 0.5 m from the ground?

  1. 5 b. 10 c. 15 d. 20

_____ 2)  An orange is hanging from the tip of a branch that is 2 meters (m) above the ground. A gust of wind blows the tree, and the orange begins to fall to the ground. Which of the following describes the orange’s energy just as the orange hits the ground?

  1. Its gravitational energy is zero
  2. Its kinetic energy is zero
  3. Its kinetic energy is twice its gravitational energy
  4. Its kinetic energy equals its gravitational energy.

_____ 3)  Which of the following is an example of gravitational potential energy changing into kinetic energy?

  1. A person riding a bicycle along a level road.
  2. Rocks falling down a mountain side
  3. Sunlight heating the water in a lake
  4. A plant producing food by photosynthesis.

_____ 4)  The Law of Conservation of energy states that

  1. The energy of a system can disappear.
  2. It is impossible to make a perpetual motion machine.
  3. Energy cannot change form
  4. Energy can neither be created nor destroyed.

_____ 5)  The Kinetic energy of an object depends on the objects ______

  1. Height b. motion c. Force d. Time

_____ 6)  Which of the following involves the conversion of chemical energy directly into light energy?

  1. Incandescent bulb
  2. Burning candle
  3. Fluorescent bulb
  4. Halogen bulb