Complete guide to "Force and Laws of Motion" for Physics students. Below you will find important questions and model answers to help you prepare.
We are building a dedicated quiz for this topic, but you can test your skills on a similar concept: NCERT-IX Gravitation: Practice Set 1.
Which of the following statement is not correct for an object moving along a straight path in an accelerated motion?
Its speed keeps changing
Its velocity always changes
It always goes away from the earth
A force is always acting on it
According to the third law of motion, action and reaction
always act on the same body
always act on different bodies in opposite directions
have same magnitude and directions
act on either body at normal to each other
A goalkeeper in a game of football pulls his hands backwards after holding the ball shot at the goal. This enables the goalkeeper to
exert larger force on the ball
reduce the force exerted by the ball on hands
increase the rate of change of momentum
decrease the rate of change of momentum
The inertia of an object tends to cause the object
to increase its speed
to decrease its speed
to resist any change in its state of motion
to decelerate due to friction
A passenger in a moving train tosses a coin which falls behind him. It means that motion of the train is
accelerated
uniform
retarded
along circular tracks
An object of mass 2 kg is sliding with a constant velocity of 4 m s–1 on a frictionless horizontal table. The force required to keep the object moving with the same velocity is
32 N
0 N
2 N
8 N
Rocket works on the principle of conservation of
mass
energy
momentum
velocity
A water tanker filled up to 2/3 of its height is moving with a uniform speed. On sudden application of the brake, the water in the tank would
move backward
move forward
be unaffected
rise upwards
There are three solids made up of aluminum, steel and wood, of the same shape and same volume. Which of them would have highest inertia?
Aluminum
Steel
Wood
All of these will have same inertia
Two balls of the same size but of different materials, rubber and iron, are kept on the smooth floor of a moving train. The brakes are applied suddenly to stop the train. Will the balls start rolling? If so, in which direction? Will they move with the same speed?
No, the balls will remain stationary.
Yes, the balls will roll forward with the same speed.
Yes, the balls will roll backward with the same speed.
Yes, the balls will roll backward, but with different speeds.
Two identical bullets are fired, one by a light rifle and another by a heavy rifle, with the same force. Which rifle will hurt the shoulder more?
The light rifle will hurt the shoulder more.
The heavy rifle will hurt the shoulder more.
Both rifles will hurt the shoulder equally.
Neither rifle will hurt the shoulder.