Question 1

If electricity costs 6.00¢/kWh (kilowatt-hour),how much would it cost you to run a 120 W stereo system 4.0 hours per day for 4.0 weeks?

Accepted Answer

A)  $0.81 
B)  $0.12 
C)  $1.38 
D)  $2.27 
A)  $0.81 
B)  $0.12 
C)  $1.38 
D)  $2.27

Question 2

A force on a particle depends on position such that F(x)= (3.00 N/m2)x2 + (6.00 N/m)x for a particle constrained to move along the x-axis. What work is done by this force on a particle that moves from x = 0.00 m to x = 2.00 m?

Accepted Answer

A)  10.0 J 
B)  20.0 J 
C)  -48.0 J 
D)  24.0 J 
E)  48.0 J 
A)  10.0 J 
B)  20.0 J 
C)  -48.0 J 
D)  24.0 J 
E)  48.0 J

Question 3

Three cars (car F,car G,and car H)are moving with the same velocity when the driver suddenly slams on the brakes,locking the wheels.The most massive car is car F,the least massive is car H,and all three cars have identical tires.
(a)Which car travels the longest distance to skid to a stop?
 A)Car F
 B)Car G
 C)Car H
 D)They all travel the same distance in stopping.
(b)For which car does friction do the largest amount of work in stopping the car?
 A)Car F
 B)Car G
 C)Car H
 D)The amount of work done by friction is the same for all cars.

Accepted Answer

The answer of Three cars (car F,car G,and car H)are...

Question 4

A car needs to generate 75.0 hp in order to maintain a constant velocity of 27.3 m/s on a flat road.What is the magnitude of the total resistive force acting on the car (due to friction,air resistance,etc.)?
(1 hp = 746 W)

Accepted Answer

A)  2.05 × 103 N 
B)  2.75 N 
C)  1.03 × 103 N 
D)  2.87 × 103 N 
A)  2.05 × 103 N 
B)  2.75 N 
C)  1.03 × 103 N 
D)  2.87 × 103 N

Question 5

A mass is pressed against (but is not attached to)an ideal horizontal spring on a frictionless horizontal surface.After being released from rest,the mass acquires a maximum speed v and a maximum kinetic energy K.If instead the mass initially compresses the spring twice as far:

Accepted Answer

A)  Its maximum speed will be 2v and its maximum kinetic energy will be 2K. 
B)  Its maximum speed will be 2v and its maximum kinetic energy will be   K. 
C)  Its maximum speed will be v   and its maximum kinetic energy will be 2K. 
D)  Its maximum speed will be 2v and its maximum kinetic energy will be 4K. 
E)  Its maximum speed will be 4v and its maximum kinetic energy will be 2K. 
A)  Its maximum speed will be 2v and its maximum kinetic energy will be 2K. 
B)  Its maximum speed will be 2v and its maximum kinetic energy will be   K. 
C)  Its maximum speed will be v   and its maximum kinetic energy will be 2K. 
D)  Its maximum speed will be 2v and its maximum kinetic energy will be 4K. 
E)  Its maximum speed will be 4v and its maximum kinetic energy will be 2K.

Question 6

A 1500-kg car accelerates from 0 to 25 m/s in 7.0 s with negligible friction and air resistance. What is the average power delivered by the engine? (1 hp = 746 W)

Accepted Answer

A)  50 hp 
B)  60 hp 
C)  70 hp 
D)  80 hp 
E)  90 hp 
A)  50 hp 
B)  60 hp 
C)  70 hp 
D)  80 hp 
E)  90 hp

Question 7

A 1000 kg car experiences a net force of 9500 N while decelerating from 30.0 m/s to 23.4 m/s.How far does it travel while slowing down?

Accepted Answer

A)  18.5 m 
B)  17.4 m 
C)  20.2 m 
D)  21.9 m 
A)  18.5 m 
B)  17.4 m 
C)  20.2 m 
D)  21.9 m

Question 8

A ball drops some distance and loses 30 J of gravitational potential energy.Do NOT ignore air resistance.How much kinetic energy did the ball gain?

Accepted Answer

A)  more than 30 J 
B)  exactly 30 J 
C)  less than 30 J 
A)  more than 30 J 
B)  exactly 30 J 
C)  less than 30 J

Exam 9: Work

If electricity costs 6.00¢/kWh (kilowatt-hour),how much would it cost you to run a 120 W stereo system 4.0 hours per day for 4.0 weeks?

A force on a particle depends on position such that F(x)= (3.00 N/m2)x2 + (6.00 N/m)x for a particle constrained to move along the x-axis. What work is done by this force on a particle that moves from x = 0.00 m to x = 2.00 m?

A car needs to generate 75.0 hp in order to maintain a constant velocity of 27.3 m/s on a flat road.What is the magnitude of the total resistive force acting on the car (due to friction,air resistance,etc.)? (1 hp = 746 W)

A mass is pressed against (but is not attached to)an ideal horizontal spring on a frictionless horizontal surface.After being released from rest,the mass acquires a maximum speed v and a maximum kinetic energy K.If instead the mass initially compresses the spring twice as far:

A 1500-kg car accelerates from 0 to 25 m/s in 7.0 s with negligible friction and air resistance. What is the average power delivered by the engine? (1 hp = 746 W)

A 1000 kg car experiences a net force of 9500 N while decelerating from 30.0 m/s to 23.4 m/s.How far does it travel while slowing down?

A ball drops some distance and loses 30 J of gravitational potential energy.Do NOT ignore air resistance.How much kinetic energy did the ball gain?

Foundations

A: Foundations

Motion in One Dimension

Acceleration

Momentum

Energy

Principle of Relativity

Interactions

Force

Motion in a Plane

Motion in a Circle

Torque

Gravity

Special Relativity

Periodic Motion

Waves in One Dimension

Waves in Two and Three Dimensions

Fluids

Entropy

Energy Transferred Thermally

Degradation of Energy

Electric Interactions

The Electric Field

Gausss Law

Work and Energy in Electrostatics

Charge Separation and Storage

Magnetic Interactions

Magnetic Fields of Charged Particles in Motion

Changing Magnetic Fields

Changing Electric Fields

Electric Circuits

Electronics

Ray Optics

Wave and Particle Optics

Filters

A force on a particle depends on position such that F(x)= (3.00 N/m²)x² + (6.00 N/m)x for a particle constrained to move along the x-axis. What work is done by this force on a particle that moves from x = 0.00 m to x = 2.00 m?