Search for notes by fellow students, in your own course and all over the country.
Browse our notes for titles which look like what you need, you can preview any of the notes via a sample of the contents. After you're happy these are the notes you're after simply pop them into your shopping cart.
Document Preview
Extracts from the notes are below, to see the PDF you'll receive please use the links above
Chapter 6 Practice Problems, Review, and Assessment
Section 1 Projectile Motion: Practice
Problems
1
...
0 m/s
from the top of a cliff that is 78
...
a
...
How far from the base of the cliff does the stone
hit the ground?
c
...
Lucy and her friend are working at an assembly
plant making wooden toy giraffes
...
If the box is
0
...
40 m away from it, what must be the horizontal
velocity of giraffes as they leave the conveyor belt?
SOLUTION:
SOLUTION:
a
...
c
...
Challenge You are visiting a friend from
elementary school who now lives in a small town
...
0 m/s to the servers
...
) If the servers catch
the sundaes 7
...
Lucy and her friend are working at an assembly
plant making wooden toy giraffes
...
If the box is
0
...
40 m away from it, what must be the horizontal
eSolutions Manual - giraffes by Cognero
velocity of Powered as they leave the conveyor belt?
SOLUTION:
4
...
0 m/s, 30
...
Find each of the following
...
Page 1
initial velocity of 27
...
0° above the horizontal,
as shown in Figure 5
...
Assume that forces from the air on the ball are
Chapter 6 Practice Problems, Review, and Assessment
negligible
...
the ball’s hang time
b
...
the horizontal distance the ball travels before
hitting the ground
SOLUTION:
a
...
5
...
0° from the
horizontal
...
6
...
0-mhigh cliff with an initial velocity of 7
...
0° above the horizontal
...
SOLUTION:
c
...
0 m/s)(cos 53
...
2 m/s
eSolutions Manual - Powered by Cognero
5
...
CHALLENGE A rock is thrown from a 50
...
0 m/s at an angle
of 53
...
Find its velocity when
it hits the ground below
...
0 m/s)(cos 53
...
2 m/s
Section 1 Projectile Motion: Review
7
...
The
faster ball crosses home plate within the strike zone,
but the slower ball is below the batter’s knees
...
8
...
It slides
off the table and lands on the floor
...
SOLUTION:
9
...
0 m/s and 20
...
How far
does the ball move horizontally before it hits the
ground?
SOLUTION:
Section 1 Projectile Motion: Review
7
...
The
faster ball crosses home plate within the strike zone,
but the slower ball is below the batter’s knees
...
Projectile Motion A tennis ball is thrown out a
window 28 m above the ground at an initial velocity
of 15
...
0° below the horizontal
...
Projectile Motion A softball player tosses a ball
into the air with an initial velocity of 11
...
What will be the ball’s maximum
height?
SOLUTION:
SOLUTION:
10
...
0 m/s, as
shown in Figure 7
...
Critical Thinking Suppose an object is thrown with
the same initial velocity and direction on Earth and on
the Moon, where the acceleration due to gravity is
one-sixth its value on Earth
...
A runner moving at a speed of 8
...
What is the centripetal
acceleration of the runner, and what agent exerts the
centripetal force on the runner?
SOLUTION:
eSolutions Manual - Powered by Cognero
Page 4
Chapter 6 Practice Problems, Review, and Assessment
Section 2 Circular Motion: Practice
Problems
12
...
8 m/s rounds a bend
with a radius of 25 m
...
A 16-g ball at the end of a 1
...
It revolves every 1
...
What is the
magnitude of the string’s tension?
SOLUTION:
SOLUTION:
The frictional force of the track acting on the
runner’s shoes exerts the force on the runner
...
An airplane traveling at 201 m/s makes a turn
...
0 m/s ?
16
...
Find the
car’s centripetal acceleration
...
A 45-kg merry-go-round worker stands on the ride’s
platform 6
...
If her speed (vworker) as she goes around
the circle is 4
...
Main Idea If you attach a ball to a rope and swing
it at a constant speed in a circle above your head, the
ball is in uniform circular motion
...
SOLUTION:
18
...
The
walls exert the force on the clothes
...
A 16-g ball at the end of a 1
...
It revolves every 1
...
What is the
eSolutions Manual - Powered by Cognero
magnitude of the string’s tension?
SOLUTION:
19
...
Write a letter to the
editor that describes physics errors in this article
...
The
The 6 Practice Problems, Review, and Assessment
walls exert the force on the clothes
...
Centripetal Acceleration A newspaper article
states that when turning a corner, a driver must be
careful to balance the centripetal and centrifugal
forces to keep from skidding
...
SOLUTION:
There is an acceleration because the direction
of the velocity is changing
...
The road
supplies that force, and the friction between the
road and the tires allows the force to be exerted
on the tires
...
The
note should also make it clear that centrifugal
force is not a real force
...
Free-Body Diagram You are sitting in the back
seat of a car going around a curve to the right
...
What is the direction of your acceleration?
b
...
What exerts this force?
22
...
0-g stone in Figure 13
is whirled horizontally at a speed of 2
...
What is
the tension in the string?
SOLUTION:
23
...
0-m radius circle
with their backs to a wall
...
7-s period of revolution
...
Your body accelerates to the right
...
The net force is to the right
...
The car’s seat exerts the force
...
Centripetal Acceleration An object swings in a
horizontal circle, supported by a 1
...
It
completes a revolution in 2
...
What is the object's
centripetal acceleration?
24
...
3 kg
...
5 m/s around a circle with a radius of
0
...
Centripetal Force The 40
...
2 m/s
...
Critical Thinking Because of Earth’s daily
rotation, you always move with uniform circular
motion
...
The scale will record a lower
Chapter 6 Practice Problems, Review, and Assessment
25
...
What is the agent that supplies the force that
causes your centripetal acceleration? If you are
standing on a scale, how does the circular motion
affect the scale’s measure of your weight?
SOLUTION:
Earth’s gravity supplies the force that
accelerates you
...
29
...
8 m/s
...
3 m/s south
...
What is the person’s speed relative to the water?
b
...
Section 3 Relative Velocity: Practice
Problems
26
...
0 m/s
...
0 m/s relative to the bus
...
SOLUTION:
27
...
75 m/s
...
0 cm/s
...
An airplane flies due north at 150 km/h relative to the
air
...
What is the plane’s speed
relative to the ground?
SOLUTION:
SOLUTION:
28
...
5 m/s
relative to the water
...
5 m/s relative to the
shore
...
CHALLENGE The airplane in Figure 17 flies at
200
...
What is the velocity of
the plane relative to the ground if it flies during the
following wind conditions?
SOLUTION:
29
...
8 m/s
...
3 m/s south
...
What is the person’s speed
b
...
CHALLENGE The airplane in Figure 17 flies at
200
...
What is the velocity of
the plane relative to the ground if it flies during the
following wind conditions?
33
...
What is the maximum speed the
boat can obtain relative to the shore? The minimum
speed? Give the direction of the boat, relative to the
river’s current, for the maximum speed and the
minimum speed relative to the shore
...
a 50
...
a 50
...
34
...
0 m/s
...
Section 3 Relative Velocity: Review
32
...
A wind blows 25 km/h east
relative to the ground
...
Relative Velocity A fishing boat with a maximum
speed of 3 m/s relative to the water is in a river that
is flowing at 2 m/s
...
Boating You are boating on a river that flows
toward the east
...
0 m/s due north relative to the
shore
...
What is the velocity of the current?
b
...
Page 8
Chapter 6 Practice Problems, Review, and Assessment
θ = 69° west of north
35
...
Because of your knowledge of
physics, you head your boat 53° west of north and
have a velocity of 6
...
a
...
What is the speed of your boat relative to the
water?
37
...
There is a wind blowing
at 85 km/h to the east relative to the ground
...
b
...
A Plane’s Relative Velocity An airplane flies due
north at 235 km/h relative to the air
...
What are the plane’s speed and direction
relative to the ground?
SOLUTION:
36
...
8 m/s
...
62 m/s
...
Relative Velocity An airplane flies due south at
175 km/h relative to the air
...
What
are the plane’s speed and direction relative to the
ground?
39
...
You want to
reach a pier directly opposite your starting point
...
SOLUTION:
eSolutions Manual - Powered by Cognero
Page 9
SOLUTION:
Choose the component of your velocity along
θ = 6 Practice Problems, Review, and Assessment
Chapter81° north of east
39
...
You want to
reach a pier directly opposite your starting point
...
SOLUTION:
Choose the component of your velocity along
the direction of the river to be equal and
opposite to the velocity of the river
...
Some students believe the force that starts the
motion of a projectile, such as the kick given a soccer
ball, remains with the ball
...
SOLUTION:
It is not correct
...
41
...
a
...
Where is the magnitude of the horizontal velocity
component largest?
c
...
Where is the magnitude of the acceleration
smallest?
SOLUTION:
a
...
Neglecting air resistance, the horizontal
velocity at all points is the same
...
A throw, kick, or other force is
a contact force, and once there is no contact,
there is no force
...
Consider the trajectory of the cannonball shown in
Figure 19
...
Where is the magnitude of the vertical-velocity
component largest?
b
...
Where is the vertical velocity smallest?
d
...
point E
b
...
Horizontal
velocity is constant and independent of vertical
velocity
...
points B and C
d
...
42
...
SOLUTION:
After they are launched, the only force acting on
both objects is gravity
...
The object launched
horizontally immediately curves downward
...
Reverse Problem Write a physics problem with
real-life objects for which the following equations
would be part of the solution
...
SOLUTION:
Answers will vary, but a correct form of the
answer is, “A baseball is thrown horizontally at
an initial speed of 1
...
How far does it Page 10
travel horizontally before it hits the ground 8 m
below?”
immediately begin to accelerate downward, but
the object launched upward at an angle has an
initial upward velocity, causing it to go upward
Chapter then curve downward
...
43
...
Hint: The two
equations describe the same object
...
A dart player throws a dart horizontally at 12
...
The dart hits the board 0
...
How far away is the player
from the board? (Level 1)
SOLUTION:
SOLUTION:
Answers will vary, but a correct form of the
answer is, “A baseball is thrown horizontally at
an initial speed of 1
...
How far does it
travel horizontally before it hits the ground 8 m
below?”
44
...
Ignoring air resistance,
where will the plane be relative to the crate when the
crate hits the ground? Draw the path of the crate as
seen by an observer on the ground
...
The toy car in Figure 20 runs off the edge of a table
that is 1
...
The car lands 0
...
(Level 1)
SOLUTION:
The plane will be directly over the crate when
the crate hits the ground
...
The crate will look like it is
moving horizontally while falling vertically to an
observer on the ground
...
You accidentally throw your car keys horizontally at
8
...
How far from the
base of the cliff should you look for the keys?
(Level 1)
SOLUTION:
a
...
How fast was the car going on the table?
SOLUTION:
a
...
46
...
4 m/s
...
32 m below the height from
which it was thrown
...
Swimming You took a running leap off a high-diving
platform
...
8 m/s and hit the
water 2
...
How high was the platform, and
b
...
The toy car in Figure 20 runs off the edge of a table
that is 1
...
The car lands 0
...
(Level 1)
48
...
You were running at 2
...
6 s later
...
Ignore air resistance
...
How long did it take the car to fall?
b
...
49
...
0° above the
horizontal
...
(Level 2)
a
...
The target is at the height from which the arrow
was shot
...
b
...
48
...
You were running at 2
...
6 s later
...
Ignore air resistance
...
Archery An arrow is shot at 30
...
Its velocity is 49 m/s, and it hits the target
...
Archery An arrow is shot at 30
...
Its velocity is 49 m/s, and it hits the target
...
What is the maximum height the arrow will attain?
b
...
How far away is it?
50
...
If the top of the fence is at the same height as the
pitch, find the velocity of the ball when it left the bat
...
(Level 2)
SOLUTION:
SOLUTION:
a
...
50
...
If the top of the fence is at the same height as the
pitch, find the velocity of the ball when it left the bat
...
(Level 2)
SOLUTION:
eSolutions Manual - Powered by Cognero
51
...
(Level 3)
a
...
What is the horizontal distance between the plane
and the victims when the box is
dropped?
SOLUTION:
a
...
At-Sea Rescue An airplane traveling 1001 m above
the ocean at 125 km/h is going to drop a box of
supplies to shipwrecked victims below
...
How many seconds before the plane is directly
overhead should the box be dropped?
b
...
Jump Shot A basketball player is trying to make a
half-court jump shot and releases the ball at the
height of the basket
...
0° above the horizontal and a
horizontal distance of 14
...
What
speed must the player give the ball in order to make
the shot? (Level 3)
SOLUTION:
SOLUTION:
a
...
52
...
If the rocks below the cliff extend
outward for 23 m, what is the minimum horizontal
velocity a diver must have to clear the rocks?
(Level 3)
SOLUTION:
54
...
Draw separate graphs of y
versus t and x versus t for each ball
...
Jump Shot A basketball player is trying to make a
half-court jump shot and releases the ball at the
height of the basket
...
0° above the horizontal and a
horizontal distance of 14
...
What
speed must the player give the ball in order to make
SOLUTION:
Page 14
Chapter 6 Practice Problems, Review, and Assessment
54
...
Draw separate graphs of y
versus t and x versus t for each ball
...
Can you go around a curve with the following
acceleration? Explain
...
zero acceleration vector
b
...
No, going around a curve changes the
direction of velocity
...
b
...
56
...
57
...
a
...
What exerts the force?
c
...
Chapter Assessment
Section 2 Circular Motion: Mastering
Concepts
55
...
a
...
constant acceleration vector
SOLUTION:
a
...
Thus, the acceleration
cannot be zero
...
No, the Powered by Cognero
constant, but the direction of the acceleration
changes
...
The force is along the string toward the
center of the circle that the yo-yo follows
...
The string exerts the force
...
If the string were released, the velocity of the
yo-yo would not change
...
There would be a gravitational force on it, so
according to Newton’s second law of motion, it
would also have a downward acceleration
...
Chapter Assessment
Section 2 Circular Motion: Mastering
Problems
58
...
3 s around a circular track that has a 15
Page
radius of 50
...
Assume that the car moves at a
constant speed
...
There would be a gravitational force on it, so
according to Newton’s second law of motion, it
Chapter 6 Practice Problems, Review, and Assessment
would also have a downward acceleration
...
Chapter Assessment
Section 2 Circular Motion: Mastering
Problems
58
...
3 s around a circular track that has a
radius of 50
...
Assume that the car moves at a
constant speed
...
What is the acceleration of the car?
b
...
59
...
Specifically indicate any ties
...
50-kg stone moving in a circle of radius 0
...
0 m/s
B: a 0
...
2 m
at a speed of 3
...
60-kg stone moving in a circle of radius 0
...
4 m/s
D: a 0
...
2 m
at a speed of 3
...
75-kg stone moving in a circle of radius 0
...
4 m/s
SOLUTION:
b
...
Ranking Task Rank the following objects according
to their centripetal accelerations, from least to
greatest
...
(Level 2)
A: a 0
...
6 m
at a speed of 2
...
50-kg stone moving in a circle of radius 1
...
0 m/s
C: a 0
...
8 m
at a speed of 2
...
75-kg stone moving in a circle of radius 1
...
0 m/s
E: a 0
...
6 m
at a speed of 2
...
Hammer Throw An athlete whirls a 7
...
8 m from the axis of rotation in a
horizontal circle, as shown in Figure 22
...
0 s, what is the
centripetal acceleration of the hammer? What is the
tension in the chain? (Level 1)
Page 16
Chapter 6 Practice Problems, Review, and Assessment
Chapter Assessment
Section 2 Circular Motion: Mastering
Problems
60
...
00-kg
hammer 1
...
If the
hammer makes one revolution in 1
...
A rotating rod that is 15
...
The other end of the
rod has a constant speed of 2010 m/s (4500 mph)
...
What is the centripetal acceleration of the end of
the rod?
b
...
0-g object to the end of
the rod, what force would be needed to hold it on the
rod?
SOLUTION:
a
...
SOLUTION:
62
...
If the
loop has a radius of 18 m, what is the slowest speed
the rider can have at the top of the loop so that the
motorcycle stays in contact with the track and avoids
falling? Hint: At this slowest speed, the track
exerts no force on the motorcycle at the top of the
loop
...
A rotating rod that is 15
...
The other end of the
rod has a constant speed of 2010 m/s (4500 mph)
...
What is the centripetal acceleration of the end of
the rod?
b
...
0-g object to the end of
the rod, what force would be needed to hold it on the
rod?
SOLUTION:
a
...
63
...
At the top of the loop, when the plane is
completely upside-down for an instant, the pilot hangs
freely in the seat and does not push against the seat
belt
...
What is
the radius of the plane’s loop? (Level 3)
Page 17
Chapter 6 Practice Problems, Review, and Assessment
63
...
At the top of the loop, when the plane is
completely upside-down for an instant, the pilot hangs
freely in the seat and does not push against the seat
belt
...
What is
the radius of the plane’s loop? (Level 3)
car to your car can be found by adding the
magnitudes of the two cars’ velocities together
...
Chapter Assessment
Section 3 Relative Velocity: Mastering
Problems
65
...
Odina will run down the shore to a
dock, 1
...
LaToya will also race to the dock and back, but she
will row a boat in the river, which has a current of
2
...
If Odina’s running speed is equal to
LaToya’s rowing speed in still water, which is
4
...
(Level 1)
SOLUTION:
SOLUTION:
Chapter Assessment
Section 3 Relative Velocity: Mastering
Concepts
64
...
Crossing a River You row a boat, such as the one
in Figure 24, perpendicular to the shore of a river
that flows at 3
...
The velocity of your boat is
4
...
(Level 2)
SOLUTION:
The magnitude of the relative velocity of that
car to your car can be found by adding the
magnitudes of the two cars’ velocities together
...
Chapter Assessment
Section 3 Relative Velocity: Mastering
Problems
65
...
Odina will run down the shore to a
dock, 1
...
eSolutions Manual - Powered by Cognero
LaToya will also race to the dock and back, but she
will row a boat in the river, which has a current of
2
...
If Odina’s running speed is equal to
a
...
What is the component of your velocity parallel to
Page 18
the shore? Perpendicular to it?
SOLUTION:
Chapter 6 Practice Problems, Review, and Assessment
66
...
0 m/s
...
0 m/s relative to the water
...
67
...
0 h
...
0 km/h
...
What is the velocity of your boat relative to the
shore?
b
...
68
...
7 m/s…
...
A possible form of the
correct answer is, “
...
If she rows at a speed of 5 m/s, at what angle
should she direct the boat to go straight to the
camp?”
b
...
Air Travel You are piloting a small plane, and you
want to reach an airport 450 km due south in 3
...
A wind is blowing from the west at 50
...
What
heading and airspeed should you choose to reach
your destination in time? (Level 2)
SOLUTION:
eSolutions Manual - Powered by Cognero
Chapter Assessment
Section 3 Relative Velocity: Applying
Concepts
69
...
How will projectile motion be affected when drag
due to air resistance is taken into consideration?
(Level 1)
SOLUTION:
The horizontal motion is uniform because there
are no forces acting in that direction (ignoring
friction)
...
The projectile-motion
equations in this book do not hold when friction
is taken into account
...
Page 19
70
...
The ball is
correct answer is, “
...
If she rows at a speed of 5 m/s, at what angle
should she direct the boat to go straight to the
Chapter 6 Practice Problems, Review, and Assessment
camp?”
Chapter Assessment
Section 3 Relative Velocity: Applying
Concepts
69
...
How will projectile motion be affected when drag
due to air resistance is taken into consideration?
(Level 1)
SOLUTION:
The horizontal motion is uniform because there
are no forces acting in that direction (ignoring
friction)
...
The projectile-motion
equations in this book do not hold when friction
is taken into account
...
70
...
The ball is
caught by the catcher at the same height at which it
was hit
...
(Level 1)
SOLUTION:
20 m/s downward
SOLUTION:
Because of the acceleration due to gravity, the
baseball falls a greater distance during the
second s than during the first s
...
You throw a rock horizontally
...
(Level 1)
a
...
b
...
The time does not change
...
b
...
73
...
The barrel of the gun is
horizontal
...
Will the dart hit the
monkey? Ignore air resistance
...
The vertical
acceleration of the dart is the same as that of
the monkey
...
71
...
Assuming that such a pitch is thrown
horizontally, compare the distance the ball falls in the
first s with the distance it falls in the second s
...
72
...
In a second horizontal
throw, you throw the rock harder and give it even
more speed
...
How will the time it takes the rock to hit the
ground be affected? Ignore air resistance
...
How will the increased speed affect the distance
from where the rock left your hand to where the
rock hits the ground?
SOLUTION:
eSolutions Manual - Powered not change
...
The time does by Cognero
The time it takes
to hit the ground depends only on vertical
velocities and acceleration
...
Football A quarterback throws a football at 24 m/s
at a 45° angle
...
0 s to reach the
top of its path and the ball is caught at the same
height at which it is thrown, how long is it in the air?
Ignore air resistance
...
0 s: 3
...
0 s down
75
...
Does the
height that you reach make any difference to your
jump? What influences the length of your jump?
(Level 1)
SOLUTION:
Both speed and angle of launch matter, so
height does make a difference
...
For this
reason, height and speed affect the range
...
Driving on a Freeway Explain why it is that when
you pass a car going in the same direction as you on
height at which it is thrown, how long is it in the air?
Ignore air resistance
...
0 s: 3
...
0 s down
75
...
Does the
height that you reach make any difference to your
jump? What influences the length of your jump?
(Level 1)
SOLUTION:
Both speed and angle of launch matter, so
height does make a difference
...
For this
reason, height and speed affect the range
...
Driving on a Freeway Explain why it is that when
you pass a car going in the same direction as you on
the freeway, it takes a longer time than when you
pass a car going in the opposite direction
...
The
passing with the lesser relative speed will take
longer
...
b
...
A top view would show the
ball moving straight while you and the car
moved out from under the ball
...
You swing one yo-yo around your head in a
horizontal circle
...
How do the
tensions in the strings differ? (Level 2)
SOLUTION:
79
...
Draw a free-body diagram of a car on a
banked curve
...
(Level 3)
a
...
Can you have such a force without friction?
SOLUTION:
77
...
(Level 2)
a
...
If the car rounds a curve at a constant speed,
where will the ball land?
SOLUTION:
a
...
b
...
A top view would show the
ball moving straight while you and the car
moved out from under the ball
...
You swing one yo-yo around your head in a
horizontal circle
...
How do the
tensions in the strings differ? (Level 2)
SOLUTION:
eSolutions Manual - Powered by Cognero
79
...
The component of the normal force acting
toward the center of the curve, and depending
on the car’s speed, the component of the
friction force acting toward the center, both
contribute to the net force in the direction of
acceleration
...
Yes, the centripetal acceleration need only
be due to the normal force
...
Early skeptics of the idea of a rotating Earth said that
the fast spin of Earth would throw people at the
equator into space
...
38×10 km
...
(Level 1)
a
...
the force needed to accelerate the person in the
circle
c
...
the normal force of Earth on the person, thatPage 21
is,
the person’s apparent weight
friction force acting toward the center, both
contribute to the net force in the direction of
acceleration
...
Yes, the centripetal acceleration need only
Chapter 6 Practice Problems, Review, and Assessment
be due to the normal force
...
Early skeptics of the idea of a rotating Earth said that
the fast spin of Earth would throw people at the
equator into space
...
38×10 km
...
(Level 1)
a
...
the force needed to accelerate the person in the
circle
c
...
the normal force of Earth on the person, that is,
the person’s apparent weight
SOLUTION:
a
...
Rocketry A rocket in outer space that is moving at
a speed of 1
...
Hot gases are expelled out the back at
2
...
What is the speed of
the gases relative to the observer? (Level 1)
SOLUTION:
83
...
13-kg ball is swung vertically from a 0
...
4 m/s
...
c
...
81
...
What is the
missile’s speed relative to the ground? (Level 1)
84
...
0 m, are running
toward each other, each moving with a constant
speed of 2
...
A dragonfly, moving with a
constant speed of 3
...
It continues to fly
back and forth until the dogs run into each other
...
Rocketry A rocket in outer space that is moving at
a speed of 1
...
Hot gases are expelled out the back at
2
...
What is the speed of
the gases relative to the observer? (Level 1)
SOLUTION:
eSolutions Manual - Powered by Cognero
85
...
If the
speed limit for a particular curve of radius 36
...
7 m/s (35 mph), at what angle should the road be
banked so that cars will stay on a circular path even
if there were no friction between the road and the
Page
tires? If the speed limit was increased to 20
...
Banked Roads Curves on roads often are banked
to help prevent cars from slipping off the road
...
0 m is
15
...
1 m/s
(45 mph), at what angle should the road be banked?
(Level 2)
86
...
45-kg ball in Figure 25 is suspended from a
0
...
(Level 3)
SOLUTION:
a
...
What is the speed of the ball?
SOLUTION:
a
...
86
...
45-kg ball in Figure 25 is suspended from a
0
...
(Level 3)
eSolutions Manual - Powered by Cognero
87
...
0° above the horizontal with an initial
speed of 22
...
The outfielder starts running as
soon as the ball is hit at a constant velocity of 2
...
Assuming that the ball is
caught at the same height at which it was hit, what
Page 23
was the initial separation between the hitter and
outfielder? Hint: There are two possible answers
...
A baseball is hit directly in line with an outfielder at
an angle of 35
...
0 m/s
...
5 m/s
and barely catches the ball
...
(Level 3)
SOLUTION:
For Shifty to easily catch the bag, the balloon
must cross the path of the bag
...
A Jewel Heist You are serving as a technical
consultant for a locally produced cartoon
...
Crafty has the jewels when the police
start to chase him
...
0-m tall
building in his attempt to escape
...
0 m from
the base of the building and untethers it, so it begins
to rise at a constant speed
...
3 m/s just as the
balloon begins its ascent
...
That is, at one
instant in time (tcatch),
eSolutions Manual - Powered by Cognero
Chapter Assessment: Thinking
Critically
89
...
Are the cars traveling through
the loop in uniform circular motion? Explain
...
Page 24
90
...
Apply Concepts Consider a roller-coaster loop like
the one in Figure 26
...
SOLUTION:
The vertical gravitational force changes the
speed of the cars, so the motion is not uniform
circular motion
...
Apply Computers and Calculators A baseball
player hits a belt-high (1
...
The player hits the ball with an initial
velocity of 42
...
The left-field wall is 96
...
Write the
equation for the height of the ball (y) as a function of
its distance from home plate (x)
...
Trace
along the path to find how high above the ground the
ball is when it is at the wall
...
Is the hit a home run?
b
...
If the initial velocity of the ball is 42
...
(Extra digits are carried to avoid roundoff
error
...
c
...
91
...
For
example, if a rocket moving at speed vA releases a
missile that has speed vB relative to the rocket, then
the speed of the missile relative to an observer that is
at rest is given by
, where c is the
8
speed of light, 3
...
This formula gives the
correct values for objects moving at slow speeds as
well
...
What speed would an
unmoving observer find for the laser light? Suppose
that a rocket moves at a speed , half the speed of
light, and shoots a missile forward at a speed of
relative to the rocket
...
91
...
For
example, if a rocket moving at speed vA releases a
missile that has speed vB relative to the rocket, then
the speed of the missile relative to an observer that is
at rest is given by
, where c is the
8
speed of light, 3
...
This formula gives the
correct values for objects moving at slow speeds as
well
...
What speed would an
unmoving observer find for the laser light? Suppose
that a rocket moves at a speed , half the speed of
light, and shoots a missile forward at a speed of
relative to the rocket
...
Analyze and Conclude A ball on a light string
moves in a vertical circle
...
Be sure to consider the effects
of gravity and tension
...
SOLUTION:
It is not uniform circular motion
...
Therefore, the centripetal
acceleration needed to keep it moving in a
circle will be larger at the bottom and smaller at
the top of the circle
...
At the bottom,
gravity is outward while the tension is inward
...
Chapter Assessment: Writing in
Physics
93
...
Research and
explain the physics behind this design choice
...
Students should explain that
the clothoid shape reduces the centripetal
acceleration experienced by the riders, making
the ride safer
...
Many amusement-park rides utilize centripetal
acceleration to create thrills for the park’s
customers
...
92
...
Analyze and describe the
motion of this system
...
Is this system in uniform
circular motion? Explain your answer
...
Gravity
increases the speed of the ball when it moves
downward and reduces the speed when it is
moving upward
...
At the top, tension and
gravity are in the same direction, so the tension
needed will be even smaller
...
SOLUTION:
Answers will vary
...
Riders on a carousel are in circular motion at a
constant speed, but because their direction
changes, they experience centripetal
acceleration
...
Multiply or divide, as indicated, using significant
figures correctly
...
(5×10 m)(4
...
Riders on a carousel are in circular motion at a
constant speed, but because their direction
Chapter 6 Practice Problems, centripetal Assessment
changes, they experience Review, and
acceleration
...
Multiply or divide, as indicated, using significant
figures correctly
...
(5×10 m)(4
...
(1
...
5×10–6 km)
4
a
...
1
...
2
...
1
...
Plot the data in Table 1 on a position-time graph
...
0 s and 5
...
3 3
c
...
6×10 kg)/(9
...
(6
...
8×102 s)
SOLUTION:
16
2
a
...
1
...
2
...
1
...
Plot the data in Table 1 on a position-time graph
...
0 s and 5
...
SOLUTION:
eSolutions Manual - Powered by Cognero
97
...
Carlos, with mass 17
...
Ricardo
pushes the 12
...
Carlos and his older brother Ricardo are at the
grocery store
...
0 kg, likes to
hang on the front of the cart while Ricardo pushes it,
even though both boys know this is not safe
...
4-kg cart with his brother on it such
2
that they accelerate at a rate of 0
...
a
...
What is the force the cart exerts on Carlos?
SOLUTION:
a
...
b
...
eSolutions Manual - Powered by Cognero
Page 28