Applied Mechanics MCQs

Question 1

A marble ball is rolled on a smooth floor of a room to hit a wall. If the time taken by the ball in returning to the point of projection is twice the time taken in reaching the wall, the coefficient of restitution between the ball and the wall, is

Accepted Answer

0.5

Answer

0.25

Answer

0.75

Answer

1.0.

Question 2

If a ball which is dropped from a height of 2.25 m on a smooth floor attains the height of bounce equal to 1.00 m, the coefficient of the restitution between the ball and floor, is

Accepted Answer

0.5

Answer

0.25

Answer

0.67

Answer

0.33

Question 3

A ball moving with a velocity of 5 misec impinges a fixed plane at an angle of 45? and its direction after impact is equally inclined to the line of impact. If the coefficient of restitution is 0.5, the velocity of the ball after impact will be

Accepted Answer

2.5 m/sec

Answer

0.5 m/sec

Answer

1.5 m/sec

Answer

3.5 m/sec

Question 4

Pick up the correct statement from the following. A rubber ball when strikes a wall rebounds but a lead ball of same mass and velocity when strikes the same wall, falls down

Accepted Answer

none of these.

Answer

rubber and lead balls undergo equal changes in momentum

Answer

chanw in momentum suffered by lead ball is less that of rubber ball

Answer

momentum of rubber ball is less than that of lead ball

Question 5

Pick up the correct statement from the following. The kinetic energy of a body

Accepted Answer

before impact is more than that after impact

Answer

before impact is equal to that after impact

Answer

before impact is less than that after impact

Answer

remains constant

Question 6

Newtons's Law of Motion is :

Accepted Answer

All the above.

Answer

Every body continues in its state of rest or of uniform motion, in a straight line, unless it is acted upon by some external force

Answer

The rate of change of momentum is directly proportional to the impressed force, and takes place in the same direction, in which the force acts

Answer

To every action, there is always an equal and opposite reaction

Question 7

The inherent property of a body which offers reluctance to change its state of rest or uniform motion, is

Accepted Answer

interia

Answer

weight

Answer

mass

Answer

momentum.

Question 8

If the gravitational acceleration at any place is doubled, the weight of a body, will

Accepted Answer

be doubled

Answer

be reduced to half

Answer

not be affected

Answer

none of these.

Question 9

The tension in a cable supporting a lift

Accepted Answer

is less when the lift is moving downwards.

Answer

is more when the lift is moving downwards

Answer

is less when the lift is moving upwards

Answer

remains constant whether it moves downwards or upwards