Name
Period
Date
Energy Worksheet 2
Energy Transfer and Storage
For each situation shown below:
1. Show your choice of system, unless it is specified for you.
**Always include the Earth in your system.
2. Decide if your system is frictionless or not, and state this.
3. Sketch an energy bar graph for the initial situation.
4. Then complete the analysis with final internal energy bar graphs and energy flow diagram.
1. System = ______________________
Friction?
Initial
Ek Eg Ee
Energy Flow
Diagram
Final
E k Eg Ee E d i s s
Final
0
Initial
0
2. System = ______________________
Friction?
Initial
Ek Eg Ee
Energy Flow
Diagram
Ek
Fina l
Eg Ee E d i s s
Ek
Final
Eg Ee E d i s s
Final
Initial
0
0
3. A car rolls to a stop while moving up a hill.
System = ______________________
Initial
Ek Eg Ee
vf = 0
yf > 0
Energy Flo w
Diagram
vi>0
yi=0
0
0
Energy WS 2
page 2
4. A person pushes a car, with the parking brake on, up a hill.
System = ______________________
yyff >>00
vvff == 00
y
yi = 0
vi = 0
Initial
Ek Eg Ee
Energy Flow
Diagram
Ek
Fina l
Eg Ee E d i s s
0
0
0
5. A load of bricks rests on a tightly coiled spring, and then is launched into the air.
System = ______________________
y
Initial
Ek Eg Ee
vf Final
yi = 0
vi = 0
0
Energy Flow
Diagram
Ek
0
Final
Eg Ee E d i s s
0
Initial
6. A crate is propelled up a hill by a tightly coiled spring.
System = ______________________
y
vf > 0
yi = 0
vi = 0
0
Initial
Initial
Ek Eg Ee
Friction? ____
Energy Flow
Diagram
Ek
Final
0
0
Final
Eg Ee E d i s s
Energy WS 2
page 3
7. A bungee jumper falls off the platform and reaches the limit of stretch of the cord.
System = ______________________
y
Initial
Ek Eg Ee
0
Initial
Final
Energy Flow
Diagram
Ek
vf = 0 0
a
Final
Eg Ee E d i s s
0
8. An elevator, initially moving downward, is brought gently to rest on the ground floor.
System = Elevator Car, Earth (not the motor!)
motor
system
boundary
y
Initial
yi > 0
Ek Eg Ee
vi > 0
0
yf = 0
vf = 0
Energy Flow
Diagram
0
Ek
Fina l
Eg Ee E d i s s
0
9. A car skids from a high speed to a stop with its brakes applied. The initial state is the car
traveling at a high speed and the final state is the car at rest.
System = ______________________
Initial
Ek Eg Ee
0
Energy Flo w
Diag ram
Final
E k Eg Ee E d i s s
0
Energy WS 2
page 4
10. Ben Laborin applies a force to push a crate from the bottom of an inclined plane to the top at a
constant speed. The initial state is the crate in motion at the bottom of the hill and the final
state is the crate in motion at the top of the hill. Ignore frictional effects.
System = ______________________
Initial
Ek Eg Ee
Energy Flo w
Diag ram
0
Final
E k Eg Ee E d i s s
0
11. A moving cross-country skier skis from the top of a hill down into a valley and up a second
smaller hill. The initial state is the skier in motion on top of the first hill and the final state is the
skier in motion on top the second hill. Ignore the effect of friction and air resistance.
System = ______________________
Initial
Ek Eg Ee
Energy Flo w
Diag ram
0
Final
E k Eg Ee E d i s s
0
12. Create your own, school appropriate, situation and construct corresponding energy bar graphs
and energy flow diagram. Try to create a situation in which work is done!
System = ______________________
Initial
Ek Eg Ee
0
Energy Flo w
Diag ram
Ek
0
Final
Eg Ee E d i s s