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


1.

Speed is
a.  a measure of how fast something is moving.  b.  always measured in
terms of a unit of distance divided by a unit of time.  c.  the distance covered per unit
time.  d.  all of the above.  e.  none of the
above. 


2.

One possible unit of speed is
a.  miles per hour.  b.  light years per century.  c.  kilometers per
hour.  d.  all of the above.  e.  none of the
above. 


3.

When you look at the speedometer in a moving car, you can see the car's
a.  average distance traveled.  b.  instantaneous acceleration.  c.  average
speed.  d.  instantaneous speed.  e.  average
acceleration. 


4.

Acceleration is defined as the CHANGE in
a.  time it takes to move from one place to another place.  b.  velocity of an
object.  c.  distance divided by the time interval.  d.  velocity divided by the time
interval.  e.  time it takes to move from one speed to another
speed. 


5.

Suppose you are in a car that is going around a curve. The speedometer reads a
constant 30 miles per hour. Which of the following is NOT true?
a.  You and the car are accelerating.  b.  Your speed is constant.  c.  Your velocity is
constant.  d.  Your direction is changing. 


6.

A train travels 6 meters in the first second of travel, 6 meters again during
the second second of travel, and 6 meters again during the third second. Its acceleration is
a.  0 m/s^{2}.  b.  6 m/s^{2}.  c.  12
m/s^{2}.  d.  18 m/s^{2}.  e.  none of the
above 


7.

A car starts from rest and after 7 seconds it is moving at 42 m/s. What is the
car’s average acceleration?
a.  0.17 m/s^{2}  b.  1.67 m/s^{2}  c.  6
m/s^{2}  d.  7 m/s^{2}  e.  none of the
above 


8.

As an object falls freely in a vacuum, its
a.  velocity increases.  b.  acceleration increases.  c.  both A and B.
 d.  none of the above. 


9.

In the absence of air resistance, objects fall at constant
a.  speed.  b.  velocity.  c.  acceleration.  d.  distances each successive
second.  e.  all of the above 


10.

A ball is thrown upwards and caught when it comes back down. In the absence of
air resistance, the speed of the ball when caught would be
a.  less than the speed it had when thrown upwards.  b.  more than the speed
it had when thrown upwards.  c.  the same as the speed it had when thrown
upwards. 


11.

Suppose an object is in free fall. Each second the object falls
a.  the same distance as in the second before.  b.  a larger distance
than in the second before.  c.  with the same instantaneous
speed.  d.  with the same average speed.  e.  none of the
above 


12.

If you drop a feather and a coin at the same time in a tube filled with air,
which will reach the bottom of the tube first?
a.  The feather  b.  Neither—they will both reach the bottom
at the same time.  c.  The coin 


13.

A ball tossed vertically upward rises, reaches its highest point, and then falls
back to its starting point. During this time the acceleration of the ball is always
a.  in the direction of motion.  b.  opposite its velocity.  c.  directed
downward.  d.  directed upward. 


14.

When a basketball player jumps to make a shot, once the feet are off the floor,
the jumper's acceleration
a.  varies with body orientation.  b.  depends on launch speed.  c.  is usually greater
for taller players (but not always).  d.  depends on all the above.  e.  is g; no
more, no less. 


15.

Suppose you take a trip that covers 180 km and takes 3 hours to make. Your
average speed is
a.  30 km/h.  b.  60 km/h.  c.  180
km/h.  d.  360 km/h.  e.  540 km/h. 


16.

Suppose a car is moving in a straight line and steadily increases its speed. It
moves from 35 km/h to 40 km/h the first second and from 40 km/h to 45 km/h the next second. What is
the car's acceleration?
a.  5 km/h·s  b.  10 km/h·s  c.  35
km/h·s  d.  40 km/h·s  e.  45 km/h·s 


17.

A ball is thrown straight up. At the top of its path its instantaneous speed is
a.  0 m/s.  b.  about 5 m/s.  c.  about 10
m/s.  d.  about 20 m/s.  e.  about 50 m/s. 


18.

A ball is thrown straight up. At the top of its path its acceleration is
a.  0 m/s^{2}.  b.  about 5 m/s^{2}.  c.  about 10
m/s^{2}.  d.  about 20 m/s^{2}.  e.  about 50
m/s^{2}. 


19.

When something falls to the ground, it accelerates. This acceleration is called
the acceleration due to gravity and is symbolized by the letter g. What is the value of
g on Earth's surface?
a.  0 m/s^{2}  b.  about 5 m/s^{2}  c.  about 10
m/s^{2}  d.  about 20 m/s^{2}  e.  about 50
m/s^{2} 


20.

A car accelerates at 2 m/s^{2}. Assuming the car starts from rest, how
much time does it need to accelerate to a speed of 20 m/s?
a.  2 seconds  b.  10 seconds  c.  20
seconds  d.  40 seconds  e.  none of the
above 


21.

If a freely falling object were somehow equipped with a speedometer, its speed
reading would increase each second by
a.  about 5 m/s.  b.  about 10 m/s.  c.  about 15
m/s.  d.  a variable amount.  e.  a rate that depends on its initial
speed. 


22.

If a ball were equipped with a speedometer and allowed to fall freely on a
planet where the acceleration due to gravity is 23 m/s^{2}, the reading on the speedometer
would increase each second by
a.  a rate that depends on its initial speed.  b.  10
m/s.  c.  12 m/s.  d.  23 m/s.  e.  46
m/s. 


23.

A freely falling object starts from rest. After falling for 6 seconds, it will
have a speed of about
a.  6 m/s.  b.  30 m/s.  c.  60
m/s.  d.  300 m/s.  e.  more than 300
m/s. 


24.

A freely falling object starts from rest. After falling for 1 second, it will
have a speed of about
a.  5 m/s.  b.  10 m/s.  c.  20
m/s.  d.  40 m/s.  e.  none of the
above 


25.

If you drop a feather and a coin at the same time in a vacuum
tube, which will reach the bottom of the tube first?
a.  Neitherthey will both reach the bottom at the same time.  b.  The
coin  c.  The feather 


26.

If a projectile is fired straight up at a speed of 30 m/s, the total time to
return to its starting point is about
a.  3 second.  b.  6 seconds.  c.  30
seconds.  d.  60 seconds.  e.  not enough information to
estimate. 

True/False Indicate whether the
statement is true or false.


27.

The rate at which distance is covered is called speed.


28.

Average speed is defined as the time it takes for a trip divided by the
distance.


29.

Velocity is different from speed in that velocity is speed in a given
direction.


30.

A unit of velocity is the meter (m).


31.

The rate at which velocity changes with time is called acceleration.


32.

A unit of acceleration is meters per second (m/s).


33.

When a car rounds a corner at a constant speed, its acceleration is zero.


34.

Even though a car is slowing down, it is still
“accelerating”.


35.

A ball is thrown into the air. At the highest point, the ball has zero velocity
and zero acceleration.


36.

As a ball falls freely, the distance it falls each second is the
same.


37.

Unless stated otherwise, when we discuss the speeds of things, we mean with
respect to the center of the universe.

Essay


38.

Write a short paragraph explaining what acceleration is and why a car is
accelerating as it rounds a corner.


39.

Write a short paragraph on how fast things fall on Earth. Compare this to motion
on the moon, where the acceleration due to gravity is about 1.6 m/s^{2}.

Problem


40.

What is the average speed of a cheetah that runs 88 m in 5 seconds?


41.

A bicycle travels 15 km in 30 minutes. What is its average speed in
km/hr?


42.

What is the average acceleration of a car that goes from rest to 60 km/h in 8
seconds?


43.

A jet on an aircraft carrier can be launched from 0 to 40 m/s in 2 seconds. What
is the acceleration of the jet?


44.

A skateboarder starting from rest accelerates down a ramp at 2 m/s^{2
}for 2 s. What is the final speed of the skateboarder?


45.

An apple falls from a tree and 0.5 second later hits the ground. How fast is the
apple falling when it hits the ground?


46.

What speed must you toss a ball straight up so that it takes 4 s to return to
you?


47.

Starting from rest, a car undergoes a constant acceleration of 6
m/s^{2.}. How far will the car travel in the first second?


48.

A crate falls from a helicopter at an altitude of 1250 m. Neglecting air drag,
how long will the crate take to strike the ground?


49.

A stone is dropped from a cliff. After it has fallen 10 m, what is the
stone's velocity?
