Transcript PowerPoint for Chapter 5 Study Guide Answers

Unlike kinetic energy,
potential energy is
b. stored
Exerting a force on an
object that causes the
object to move is called
a. work
The rate at which work is
done is called
c. power
The energy associated with
motion is called
a. kinetic
energy.
What two factors affect
kinetic energy
c. mass and
speed
The law of conservation of
energy states that when one form
of energy is transformed into another,
b.no energy is destroyed
in the process.
What type of energy
powers the sun?
b. nuclear
energy.
You hit a drum and hear a
sound. What type of energy
allows you to hear the sound?
c. sound
energy.
Energy stored in the nucleus of
an atom is called
b. nuclear
energy.
Energy is the ability
to do work or cause change.
A large truck and a small car
are moving at the same speed.
The truck has greater kinetic
mass
energy because its
is greater.
A toaster transforms electrical
thermal
(heat) energy to toast
energy into
the bread.
The amount of energy
transferred in a unit of time is
called
power.
A book sitting on a shelf has
potential energy.
The SI unit for measuring
energy is
joules.
Ben and Tim race 1 lap around
a track. Tim won even though
both runners did the same
amount of
work.
Which letter represents the position at
which the basketball has the greatest
potential energy? Explain.
Point C. At this point, which is the
highest point, all of the ball’s energy
is gravitational potential energy. The
ball does not have kinetic energy
because it is not moving at this point.
Which letter represents the position at
which the basketball has the greatest
kinetic energy? Explain.
Point E. As the ball falls from C to E,
potential energy is converted to kinetic
energy. The velocity of the ball increases
as it falls, which means that the ball attains
its greatest velocity, and thus its greatest
kinetic energy, at E.
.
Which has the greater kinetic energy, a 10kg object traveling at a speed of 2 m/s or a
5-kg object traveling at a speed of 4 m/s?
Explain.
½ X 10 X 22 = ½ X 10 X 4 = ½ X 40 = 20
Joules
½ X 5 X 42 = ½ X 5 X 16 = ½ X 80 = 40 Joules
.
Is the potential energy of the
pendulum increasing or decreasing at
position E? Explain.
Neither. The potential energy of the
pendulum reaches its maximum value
at position E, and is neither increasing
nor decreasing at that point.
.
Compare the sum of the kinetic and potential
energies of the pendulum at position A to the sum at
position C. (Ignore friction.)
Point A is a point of maximum potential energy and
minimum kinetic energy. Point C is the point of
maximum kinetic energy and minimum potential
energy. According to the law of conservation of
energy, the sum of the kinetic and potential energies
of the pendulum is constant, assuming no losses
from friction. So the potential energy at A is equal to
the kinetic energy at C.
.