Homework #2

Due: 11:58pm on Monday, April 14, 2014

You will receive no credit for items you complete after the assignment is due. Grading Policy

Video Solution Problem for Chapter 12 Section 7 - Normal and Tangential Acceleration.

Watch the following video and answer the question.

Part A

The roller coaster car reaches point of the loop with speed of , which is increasing at the rate of . Determine the magnitude of the

acceleration at if .

A 20 m/s 5 m/s2

A = 25 mpA

ANSWER:

Correct

Problem 12.127

A train is traveling with a constant speed of = 13 along the curved path.

= 16.8 aAms2

= 5.00 aAms2

= 16.0 aAms2

= 20.0 aAms2

vt m/s

Part A

Determine the magnitude of the acceleration of the front of the train, , at the instant it reaches point .

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Problem 12.133

Car turns such that its speed is increased by , where is in seconds.

Part A

B A (y = 0)

= 4.33 ams2

B ( = (0.5 )m/at)B et s2 t

If the car starts from rest when = 0 , determine the magnitude of its velocity when = 2 . Neglect the size of the car.

Express your answer with the appropriate units.

ANSWER:

Correct

Part B

Determine the magnitude of its acceleration when = 2 .

Express your answer with the appropriate units.

ANSWER:

Correct

Problem 12.144

The Ferris wheel turns such that the speed of the passengers is increased by , where is in seconds. The wheel starts from rest when = 0 .

t s

= 3.19 vms

t s

= 4.22 ams2

= (4t)ft/v s2 t

Part A

Determine the magnitude of the velocity of the passengers when the wheel turns = 30 .

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Part B

Determine the magnitude of the acceleration of the passengers when the wheel turns = 30 .

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Video Solution Problem for Chapter 12 Section 8 - Cylindrical Components of Particle Motion.

Watch the following video and answer the question.

= 19.9 v fts

= 16.0 afts2

Part A

The slotted link is pinned at , and as a result of rotation it drives the peg along the horizontal guide. Compute the magnitude of the velocity and acceleration

of along the horizontal guide. Compute the magnitudes of the velocity and acceleration of as a function of if , where is measured in

seconds.

ANSWER:

Correct

O P

P P = (3t) rad t

v = 1.500 se m/s, a = 9.00 se tan m/c2 c2 s2

v = 1.500 sec tan m/s, a = 9.00 sec tan m/s2

v = 0.500 se m/s, a = 1.000 se tan m/c2 c2 s2

v = 1.500 sec m/s, a = 9.00 sec tan m/s2

Problem 12.170

A particle is moving along a circular path having a radius of 5.9 such that its position as a function of time is given by , where and the argument for the

sine are in radians, and is in seconds.

Part A

Determine the acceleration of the particle at = 34 . The particle starts from rest at .

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Problem 12.180

Pin P is constrained to move along the curve defined by the lemniscate .

in. = sin 3t t

= 0

= 46.7 ains2

r = (4 sin 2) ft

Part A

If the slotted arm OA rotates counterclockwise with a constant angular velocity of = 1.5 , determine the magnitude of the velocity of peg P when = 63

.

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Part B

Determine the magnitude of the acceleration of peg P when = 63 .

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Video Solution Problem for Chapter 12 Section 9 - Velocity Kinematics of a Pulley System.

Watch the following video and answer the question.

rad/s

= 8.56 v fts

= 42.1 afts2

Part A

The mine car is being pulled up to the inclined plane using the motor and the rope-and-pulley arrangement shown. Determine the speed at which a point

on the cable must be traveling toward the motor to move the car up the plane with a constant speed of .

ANSWER:

Correct

Problem 12.202

The cable is drawn into the motor with an acceleration of 0.4 .

M vp P

v = 5 m/s

= 2.50 m/sVP

= 15.00 m/sVP

= 1.667 m/sVP

= 10.00 m/sVP

m/s2

Part A

Determine the time needed for the load at to attain a speed of 6 , starting from rest.

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Video Solution Problem for Chapter 12 Section 10 - Relative Velocity and Acceleration.

Watch the following video and answer the question.

B m/s

= 60.0 t s

Part A

At the instant shown, cars and are traveling at speeds of and , respectively. If is accelerating at while maintains a

constant speed, determine the magnitudes of the velocity and acceleration of with respect to .

A B 20 mi/h 45 mi/h B 1600 mi/h2 A

A B

ANSWER:

Correct

Problem 12.208

Part A

If block is moving downward at 6 while block is moving down at 18 , determine the speed of block .

Express your answer with the appropriate units.

ANSWER:

= 33.9 mi/h, = 1600 mi/vA/B aA/B h2

= 60.8 mi/h, = 1426 mi/vA/B aA/B h2

= 33.9 mi/h, = 1426 mi/vA/B aA/B h2

= 60.8 mi/h, = 1600 mi/vA/B aA/B h2

A ft/s C ft/s B

Correct

Problem 12.222

Two planes, and , are flying at the same altitude. Their velocities are = 560 and = 480 such that the angle between their straight-line courses

is = 75 .

Part A

Determine the magnitude of the velocity of plane with respect to plane .

Express your answer to three significant figures and include the appropriate units.

ANSWER:

= 12.0 vBfts

A B vA km/h vB km/h

B A

= 827 vB/Akmh

Correct

Part B

Determine the angle of (clockwise from the negative axis).

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Problem 12.229

Cars and are traveling around the circular race track. At the instant shown, has a speed of 86 and is increasing its speed at the rate of 15 ,

whereas has a speed of 113 and is decreasing its speed at 25 .

v vB/A x

= 40.9 v

A B A ft/s ft / s2

B ft/s ft / s2

Part A

Determine the relative velocity of car with respect to car at this instant.

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Part B

Determine the angle of (counterclockwise from the negaitive axis).

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Part C

Determine the relative acceleration of car with respect to car at this instant.

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

A B

= 102 vA/B fts

v vA/B x

= 73.2 v

A B

= 28.1 aA/Bfts2

Part D

Determine the angle of (counterclockwise from the positive axis).

Express your answer to three significant figures and include the appropriate units.

ANSWER:

Correct

Problem 12.232

At the instant shown, cars and travel at speeds of 70 and 50 , respectively.

Part A

If is decreasing its speed at 1400 while is increasing its speed at 800 , determine the direction of the the acceleration of with respect to

. Car moves along a curve having a radius of curvature of 0.7 .

Express your answer with the appropriate units.

a aA/B x

= 53.4 a

A B mi/h mi/h

B mi/h2 A mi/h2 B A

B mi

ANSWER:

Correct

Part B

Determine the magnitude of the the acceleration of with respect to .

Express your answer with the appropriate units.

ANSWER:

Correct

Score Summary:

Your score on this assignment is 99.7%.

You received 99.7 out of a possible total of 100 points.

= 57.8 south of east

B A

= 4490 ami

h2