PS U5 Energy Test Review

1. I can define energy, list different types of energy and describe how energy can be transformed

from one form to another.

Type of Energy / Description/Definition
Mechanical
Complete the following descriptions of energy transformations:
a. A candle burning changes ______energy into ______and ______energy.
b. A wind-up toy changes ______energy into ______energy.
c. We can see stars because they change ______energy into ______energy.
d. A plant changes ______energy into ______energy.

2. I can distinguish between elastic, chemical and gravitational potential energy.

Type of Potential Energy / Definition / Example
Elastic
Chemical
Gravitational

3. I can define gravitational potential energy and kinetic energy and use the Eg and Ek formulas to

solve problems.

Gravitational Potential Energy
Definition:
Units:
Symbol:
Equation: Triangle: / Kinetic
Definition:
Units:
Symbol:
Equation: Triangle:
Example problems:
  1. You serve a volleyball with a mass of 2.1 kg. The ball leaves your hand with a speed of 30 m/s. The ball has ______energy. Calculate it.
  2. The Eg of an apple is 6.00 joules. The apple is 3.00-meters high. What is the mass of the apple?
  3. Ima Scaared (m=56.2 kg) is traveling at a speed of 12.8 m/s at the top of a 19.5 m roller coaster loop. Determine her Ek and Eg at the top of the loop.

4. I can use words, diagrams, pie charts and energy bar graphs to analyze energy storage and

energy transfers for a system.

Energy Pie Charts

Draw Pie Charts for the following situations:
  1. You pull a wagon, initially at rest, until it reaches constant velocity, along a level sidewalk.
  1. A dart gun fired a dart straight up which then sticks to the ceiling.

Energy Bar Charts


5. I can describe 3 ways that energy can enter or leave system.

6. I can describe the law of conservation of energy.

State the Law of Conseration of Energy:
Example:
  1. A large chunk of ice with a mass of 15.0 kg falls from a roof 8.00 m above the ground. Find the kinetic energy of the ice when it reaches the ground.

7. I can define work and power and make calculations using correct formulas and units.

WORK
Definition:
Units:
Equation: Triangle: / POWER
Definition:
Units:
Equation: Triangle:
Example problems:
  1. How much work is done when you push against a wall with 50 N of force perpendicular to the wall.
  1. A 10-N force is applied to push a block across a friction free surface for a displacement of 5.0 m to the right. Which forces do work on the box? Calculate the work each force does on the box.
  1. A force of 825 N is needed to push a car across a lot. Two students push the car 35 m.
How much work is done?
After a rainstorm, the force needed to push the car doubled because the ground became soft. By what amount does the work done by the students change?
  1. Describe a situation where a force is applied but no work is being done.