Multiple Choice Identify the
choice that best completes the statement or answers the question.


1.

In which of the following sentences is work used in the everyday sense of
the word?
a.  Lifting a heavy bucket involves doing work on the bucket.  b.  The force of
friction usually does negative work.  c.  Sam and Rachel worked hard pushing the
car.  d.  Work is a physical quantity. 


2.

Work is done when
a.  the displacement is not zero.  b.  the displacement is zero.  c.  the force is
zero.  d.  the force and displacement are perpendicular. 


3.

What is the common formula for work? Assume that W is the work, F
is a constant force, v is the change in velocity, and
d is the displacement.
a.  W = FDv  c.  W =
Fd^{}  b.  W =
Fd  d.  W =
F^{}d 


4.

In which of the following scenarios is no net work done?
a.  A car accelerates down a hill.  b.  A car travels at constant speed on a flat
road.  c.  A car decelerates on a flat road.  d.  A car decelerates as it travels up a
hill. 


5.

A construction worker pushes a wheelbarrow 5.0 m with a horizontal force of 50.0
N. How much work is done by the worker on the wheelbarrow?
a.  10 J  c.  250 J  b.  55 J  d.  1250 J 


6.

Which of the following energy forms is not involved in hitting a tennis
ball?
a.  kinetic energy  c.  gravitational potential energy  b.  chemical potential
energy  d.  elastic potential
energy 


7.

Which of the following formulas would be used to directly calculate the kinetic
energy of an object with mass m bouncing up and down on a spring with spring constant
k?


8.

Which form of energy is involved in weighing fruit on a spring scale?
a.  kinetic energy  c.  gravitational potential energy  b.  nonmechanical
energy  d.  elastic potential
energy 


9.

The equation for determining gravitational potential energy is PE_{} = mgh. Which factor(s) in this equation is (are) not intrinsic to
an object?


10.

How much elastic potential energy is stored in a bungee cord with a spring
constant of 10.0 N/m when the cord is stretched 2.00 m?
a.  10.0 J  c.  40.0 J  b.  20.0 J  d.  200 J 


11.

In the presence of frictional force,
a.  nonmechanical energy is negligible and mechanical energy is no longer
conserved.  b.  nonmechanical energy is negligible and mechanical energy is
conserved.  c.  nonmechanical energy is no longer negligible and mechanical energy is
conserved.  d.  nonmechanical energy is no longer negligible and mechanical energy is no longer
conserved. 


12.

Which of the following equations is not an equation for power, P,
in terms of work, W, displacement, d, time interval, t,
force, F, and/or velocity, v?

Short Answer


13.

Is kinetic energy a vector quantity or a scalar quantity?


14.

State, in words, the workkinetic energy theorem.


15.

What quantity is the sum of the kinetic energy and all forms of potential energy
in a system?

Problem


16.

How much work is done on a bookshelf being pulled 5.00 m at an angle of
37.0° from the horizontal? The magnitude of the component of the
force that does the work is 43.0 N.


17.

A worker pushes a box with a horizontal force of 50.0 N over a level distance of
5.0 m. If a frictional force of 43 N acts on the box in a direction opposite to that of the worker,
what net work is done on the box?


18.

A 2.00 g coin, which has zero potential energy at the surface, is dropped into a
10.0 m well. After the coin comes to a stop in the mud, what is its potential energy with respect to
the surface?


19.

A pendulum with a mass of 1 kg is released from a height of 1.5 cm above the
height of its resting position. How fast will the pendulum be moving when it passes through the
lowest point of its swing?


20.

What is the average power output of a weightlifter who can lift 250 kg a height
of 2.0 m in 2.0 s?


21.

Water flows over a section of Niagara Falls at a rate of 1.20 ´ 10^{} kg/s and falls 50.0 m. What is the
power of the waterfall?
