Transcript Energy Test Review

Energy Test Review
Potential Energy
Kinetic Energy
Velocity
1. In the diagram below, the baseball
is being released by the pitcher
(position A), traveling toward the
batter (position B), and stopping in
the catcher’s glove (position C). At
which position would the baseball
have the most kinetic energy?
Answer B, Why?
In motion at this point
2. When the rubber band was
stretched, what type of
energy did it contain?
Answer: Potential Energy
3. As the rubber band was
released and snapped back, it
changed to _______ energy.
Answer: Kinetic
4. Turning on a light is what
type of energy transformation?
Answer: electric to light
5. What energy transformation
occurs when you strike a
match on the rough strip of a
matchbook cover?
Answer: Mechanical to Heat (thermal)
6. The burning match involves
the transformation of
Answer: chemical energy to light and
heat (thermal) energy
7. What type of energy is
contained in the matches
within a matchbook?
Chemical potential energy
8. Near earth’s surface, an
object’s gravitational potential
energy is determined by the
formula PE = mgh. What does
the g in the formula
represent?
g =acceleration due to gravity or
10 m/s2
9. An object’s gravitational kinetic
energy is determined by the formula
KE = ½ mv2, where v represents the
velocity of the object. If the velocity
of a thrown object were to increase,
what would happen to the kinetic
energy of the object?
Increases
10. Complete the following chart by putting in
the energy needed (input) and the energy
given off (output). Put your answers on
the answer document-not on the table
Item
.
Toaster
Fan
Telephone
Gasoline
Chainsaw
Natural gas stove
Energy input
Energy output
In doing the following inclined plane experiment
in “ideal conditions,” assume that friction from
the air, incline or floor is negligible. A stationary
box at the top of a frictionless incline is released
and is allowed to slide to the bottom. The figure
below illustrates the box in four positions
labeled A through D as it is sliding from the
incline onto the level floor. As the box moves
from the bottom of the incline to the floor,
assume that the box experiences no change in
speed, only a change in direction.
11. At what time does the box have the
greatest kinetic energy?
12. Where is the potential
energy of the box greatest?
14. When a space shuttle is launched, it continues to
accelerate for several minutes.
Which graph shows the kinetic energy of the space shuttle
during the first few minutes of flight? (Launch time = 0)
A, Why?
Calculation Problems
These problems must have work
to show how you got the answers.
Start with the formula then plug in
the values.
A marble with a mass of 0.01 kg is released to travel
through a track that was 2.00 meters long. It takes the
marble 0.930 seconds to travel the length of the track.
What is the velocity?
Velocity = distance/time
What is distance?
2.00 m
What is time?
0.930 s
V = (2.00 m) /(0.930 s) = _____ m/s
Calculate the approximate gravitational
potential energy of a 70.0-kg skier
when he is at the top of a 30.0 meter
hill.
PE = mass x g x height
Mass?
M = 70.0 kg
g=?
Acceleration due to gravity = 10 m/s2
Height = ?
H = 30.0 m
PE = (70.0 kg) x (10 m/s2) x (30.0 m) = __ J
Calculate the kinetic energy of
a 0.50-kg marble on a 3.0-m
track if the velocity is 3.5 m/s.
KE = ½ mass x velocity 2
Mass = 0.50 kg
Velocity = 3.5 m/s
KE = ½ x (0.50 kg) x (3.5 m/s)2 = ____ J
Short Answer
These should be answered with
complete sentences.
State the law of conservation
of energy.
Matter cannot be created nor destroyed;
however, it can be transferred.
State the using complete
sentences three disadvantages
and three advantages to
renewable energy sources.
You may pick a renewable energy
Solar
Wind
Water
Draw a diagram showing the circuit
of energy in a DC circuit powered by
a 1.5 volt battery and contains one
switch and one resistor (light bulb).
Show the direction of the flow of the
electrons.
+
B
A
T
T
E
R
Y
-
Flow of electrons is from the
negative battery terminal through
the light then switch then back to
the positive end of the battery
terminal.
Light
switch