Force & Laws Of Motion (Test -2) - Class 9 Science, 21-02-2018 - Class 9 MCQ

The physical quantity which is equal to the rate of change of momentum is

Which of the following is not used to reduce friction

Match the following with correct response. 
(1) Inertia 
(2) Friction 
(3) Momentum
(4) Force 

(A) Product of mass and velocity 
(B) Mass of the object 
(C) Rate of change of momentum 
(D) Necessary evil

Match the following with correct response. 
(1) Cause of acceleration 
(2) Quantitative measure of inertia 
(3) powder applied on carom board
(4) Tyres of vehicles made Rough 

(A) Mass 
(B) Increases friction 
(C) Decreases friction 
(D) Force

Which of the following physical quantity is associated with Newton’s second law of motion?

What is the momentum of an object of mass 1/2 m, moving with a velocity 2v?

Match the following with correct response. 
(1) Newton’s first law of motion 
(2) Newton’s second law of motion 
(3) Newton’s third law of motion 
(4) Galileo’s law of inertia 

(A) The acceleration produced is directly proportional to product of mass & force applied 
(B) When no force is exerted on an object it stays at rest or it moves in a straight light with constant speed 
(C) To every action there is an equal & opposite reaction 
(D) An object at rest or in uniform motion, will remain at rest or uniform motion unless an unbalanced force is applied on it

When a force is exerted on an object, it can change its-
A State 
B Position 
C Shape 
D Direction 

State whether the following statement is true or false “force can be measured using first law of motion”

“Internal forces are forces which bodies exert on each other when the bodies are part of the system” is

Match the following with correct response. 
(1) Force 
(2) Momentum 
(3) Unbalanced force 
(4) Principle on rocket works 

(A) Newton 
(B) Acceleration 
(C) Kg m/s 
(D) Newton’s third law of motion

It is advised to tie any luggage kept on the roof a bus with a rope to avoid the luggage from falling down because of

“A body moves with a constant speed of 5m/s. This shows that no unbalanced forces are acting on the body” is a

According to the law of conservation of momentum

Match the following with correct response. 
(1) Friction 
(2) Limiting friction 
(3) Sliding friction 
(4) Rolling friction 

(A) when one object rolls over another 
(B) Force just sufficient to move the object 
(C) Force which opposes motion 
(D) Force sufficient to slide one object over another

An Object moving along a straight path with an accelerated motion. The correct statement about the object- 

A Its velocity keeps changing 
B Its speed keeps changing 
C A force is always acting on it 
D Its mass keeps on changing

Same amount of force is acting on a car and bus. It the ratio of the mass of the bus and the car is 50:1, calculate the ratio of the acceleration produced in the car to the acceleration produced in the bus

A bullet of mass 10g is fired from a rifle. The bullet tales 0.003 second to move through its barrel and leaves it with a velocity of 300m|s. What is the force exerted on the bullet by the rifle?

Match the following with correct response. 
(1) Unbalanced force 
(2) Unchangingtendency 
(3) Method of reducing friction 
(4) Rate of change of momentum 

(A) Applying grease 
(B) Change in state 
(C) Force 
(D) Inertia

The passenger feels a jerk forward when a bus moving at a high speed suddenly stops. This happens due to

A force of 100N applied on an object accelerates it with an acceleration of2ms⁻². How much force is required to produce the same acceleration when identical object of same mass is tied with the first object?

A force of 5N gives a mass m1 an acceleration of 10ms-2 and mass m2 an acceleration of 20ms⁻².What acceleration would if give it both the masses were tied together?

Match the following with correct response. 
(1) F
(2) P
(3) ΔP
(4) Momentum before collision 

(A) m×v
(B) Momentum after collision are equal 

(D) m×a

Weight of a body due to the Earth acts

Which would require a greater force – accelerating a body A of mass 2kg at 5ms⁻² or a body B of mass 5kg at 2ms-2?

Statement A: Rocket contains fuel as well as oxygen to burn its fuel in its body. 
Statement B: A jet plane takes oxygen from atmosphere to burn its fuel

Which is correct about frictional force & gravitational force? 
A Friction force always produces retardation while gravitational force Produces acceleration also 
B Both produces retardation 
C Frictional for acts when two surfaces are in contact 
D Gravitational force acts when the object is at height 12