Questions about Chapter 2: Motion along a straight line.


Question  No: 1

A ball thrown vertically upward is caught by the thrower after 20 seconds. Find the initial speed of the ball.

 

A. 196 m/s

B. 98 m/s

C. 49 m/s

D. 72 m/s

E. 36 m/s


Question  No: 2

The velocity of a particle moving along the x-axis varies in the time according to the equation v = (15-8*t) m/s. Find the acceleration 'a' of the particle at t = 2 s and the average velocity '<v>' between t = 0 and t = 2 s

 

A. a = 16 m/s**2, <v> = 13 m/s

B. a = 0 m/s**2, <v> =15 m/s

C. a = 16 m/s**2, <v> = - 4 m/s

D. a =16 m/s**2, <v> = 13 m/s

E. a = -8 m/s**2, <v> = 7 m/s


Question  No: 3

When a ball is thrown upward, initially

 

A. the velocity decreases, and the acceleration is constant

B. the velocity decreases, and the acceleration increases

C. the velocity increases, and the acceleration increases

D. the velocity increases, and the acceleration decreases

E. the velocity decreases, and the acceleration is zero


Question  No: 4

A dog runs 100 m away from its master in a straight line in 8.4 s, and then runs halfway back in 2.8 s. Calculate the dog's average velocity

 

A. 8.75 m/s towards its master

B. 3.03 m/s away from its master

C. 4.46 m/s away from its master

D. 2.09 m/s away from its master

E. 8.75 m/s towards its master


Question  No: 5

The position of a particle moving along the x axis is given by x = (21 * 22t-6t**2) m, where t is in second.  What is the average velocity during the time between t = 1 second to t = 3 seconds.

 

A. -4.0 m/s

B. - 2.0 m/s

C. -6.0 m/s

D. 3.0 m/s

E. 5.0 m/s


Question  No: 6

Which of the following statement is true

 

B. Distance and displacement are both vector quantities.

C. Speed and velocity have the same meaning.

D. If and object is moving it must be accelerating.

D. when a ball thrown upward, the acceleration at tmaximum altitude is -9.8 m/s**2.

E. A car moving at 80 km/h must have an acceleration greater than one moving at 60 km/h.


Question  No: 7

An automobile starts from rest, maintains a constant acceleration of 2 m/s**2 until its speed is 20 m/s, and then continues at this constant speed.  Find the time required for the car to travel 800 m from rest.

 

A. 45 s

B. 27 s

C. 55 s

D. 25 s

E. 60 s


Question  No: 8

The position of an object moving in a straight line is given by: x = 4.0 t + t**3 , where x is in m and t in s. What is the average velocity for the time interval from t=2.0 s to t=3.0 s?

 

A. +23 ms

B. -44 m/s

C. +17 m/s

D.  -94 m/s

E. +11 m/s

 


Question  No: 9

Two subway stops are separated by 1200 m. If a train accelerates at +1.20 m/s**2 from rest through the first half of the distance, and decelerates at -1.20 m/s**2 through the second half, what is the total travel time?

 

A. 63.2 s

B. 13.6 s

C. 510 s

D. 99.4 s

E. 17.9 s

 


Question  No: 10

A particle moves along the x axis with velocity v(t) as shown in figure (3). Find the acceleration at time t=2.0 s.

 

A. -10 m/s**2

B. 0 m/s**2

C. +10 m/s**2

D. -20 m/s**2

E.+20 m/s**2

 


Question  No:11

An object (A) is thrown vertically upward with an initial velocity of 100 m/s and another object (B) with 10 m/s. The maximum heights reached by A and B are hA and hB, respectively. The ratio hA/hB is:

 

A. 100

B. 10

C. 1000

D. 1/10

E. 1/100