Question 1

Suppose that an object is moving with constant nonzero acceleration.Which of the following is an accurate statement concerning its motion?

Accepted Answer

A)  In equal times its speed changes by equal amounts. 
B)  In equal times its velocity changes by equal amounts. 
C)  In equal times it moves equal distances. 
D)  A graph of its position as a function of time has a constant slope. 
E)  A graph of its velocity as a function of time is a horizontal line. 
A)  In equal times its speed changes by equal amounts. 
B)  In equal times its velocity changes by equal amounts. 
C)  In equal times it moves equal distances. 
D)  A graph of its position as a function of time has a constant slope. 
E)  A graph of its velocity as a function of time is a horizontal line.

Question 2

A car is 200 m from a stop sign and traveling toward the sign at 40.0 m/s.At this time,the driver suddenly realizes that she must stop the car.If it takes 0.200 s for the driver to apply the brakes,what must be the magnitude of the constant acceleration of the car after the brakes are applied so that the car will come to rest at the stop sign?

Accepted Answer

A)  2.89 m/s2 
B)  3.89 m/s2 
C)  4.17 m/s2 
D)  3.42 m/s2 
E)  2.08 m/s2 
A)  2.89 m/s2 
B)  3.89 m/s2 
C)  4.17 m/s2 
D)  3.42 m/s2 
E)  2.08 m/s2

Question 3

When can we be certain that the average velocity of an object is always equal to its instantaneous velocity?

Accepted Answer

A)  always 
B)  never 
C)  only when the velocity is constant 
D)  only when the acceleration is constant 
E)  only when the acceleration is changing at a constant rate 
A)  always 
B)  never 
C)  only when the velocity is constant 
D)  only when the acceleration is constant 
E)  only when the acceleration is changing at a constant rate

Question 4

The figure represents the velocity of a particle as it travels along the x-axis.At what value (or values)of t is the instantaneous acceleration equal to zero?

Accepted Answer

A)  t = 0 
B)  t = 0.5 s and t = 2 s 
C)  t = 1 s 
A)  t = 0 
B)  t = 0.5 s and t = 2 s 
C)  t = 1 s

Question 5

An object is moving in a straight line along the x-axis.A plot of its velocity in the x direction as a function of time is shown in the figure.Which graph represents its acceleration in the x direction as a function of time?

Accepted Answer

A) 
  
B) 
  
C) 
  
D) 
  
E) 
  
A) 
  
B) 
  
C) 
  
D) 
  
E)

Question 6

Two objects have masses m and 5m,respectively.They both are placed side by side on a frictionless inclined plane and allowed to slide down from rest.

Accepted Answer

A)  It takes the lighter object 5 times longer to reach the bottom of the incline than the heavier object. 
B)  It takes the lighter object 10 times longer to reach the bottom of the incline than the heavier object. 
C)  It takes the heavier object 5 times longer to reach the bottom of the incline than the lighter object. 
D)  It takes the heavier object 10 times longer to reach the bottom of the incline than the lighter object. 
E)  The two objects reach the bottom of the incline at the same time. 
A)  It takes the lighter object 5 times longer to reach the bottom of the incline than the heavier object. 
B)  It takes the lighter object 10 times longer to reach the bottom of the incline than the heavier object. 
C)  It takes the heavier object 5 times longer to reach the bottom of the incline than the lighter object. 
D)  It takes the heavier object 10 times longer to reach the bottom of the incline than the lighter object. 
E)  The two objects reach the bottom of the incline at the same time.

Question 7

A test rocket is fired straight up from rest with a net acceleration of 20.0 m/s2.After 4.00 seconds the motor turns off,but the rocket continues to coast upward with no appreciable air resistance.What maximum elevation does the rocket reach?

Accepted Answer

A)  487 m 
B)  327 m 
C)  320 m 
D)  408 m 
E)  160 m 
A)  487 m 
B)  327 m 
C)  320 m 
D)  408 m 
E)  160 m

Question 8

The position of an object is given by x = at3 - bt2 + ct,where a = 4.1 m/s3,b = 2.2 m/s2,c = 1.7 m/s,and x and t are in SI units.What is the instantaneous acceleration of the object when t = 0.7 s?

Accepted Answer

A)  -13 m/s2 
B)  2.9 m/s2 
C)  4.6 m/s2 
D)  13 m/s2 
A)  -13 m/s2 
B)  2.9 m/s2 
C)  4.6 m/s2 
D)  13 m/s2

Exam 3: Acceleration

Suppose that an object is moving with constant nonzero acceleration.Which of the following is an accurate statement concerning its motion?

When can we be certain that the average velocity of an object is always equal to its instantaneous velocity?

The figure represents the velocity of a particle as it travels along the x-axis.At what value (or values)of t is the instantaneous acceleration equal to zero?

An object is moving in a straight line along the x-axis.A plot of its velocity in the x direction as a function of time is shown in the figure.Which graph represents its acceleration in the x direction as a function of time?

Two objects have masses m and 5m,respectively.They both are placed side by side on a frictionless inclined plane and allowed to slide down from rest.

A test rocket is fired straight up from rest with a net acceleration of 20.0 m/s2.After 4.00 seconds the motor turns off,but the rocket continues to coast upward with no appreciable air resistance.What maximum elevation does the rocket reach?

The position of an object is given by x = at3 - bt2 + ct,where a = 4.1 m/s3,b = 2.2 m/s2,c = 1.7 m/s,and x and t are in SI units.What is the instantaneous acceleration of the object when t = 0.7 s?

Foundations

A: Foundations

Motion in One Dimension

Momentum

Energy

Principle of Relativity

Interactions

Force

Work

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 test rocket is fired straight up from rest with a net acceleration of 20.0 m/s².After 4.00 seconds the motor turns off,but the rocket continues to coast upward with no appreciable air resistance.What maximum elevation does the rocket reach?

The position of an object is given by x = at³ - bt² + ct,where a = 4.1 m/s³,b = 2.2 m/s²,c = 1.7 m/s,and x and t are in SI units.What is the instantaneous acceleration of the object when t = 0.7 s?