Laws of Motion MCQs : This section focuses on the "Laws of Motion" in Physics Class 11. These Multiple Choice Questions (MCQs) should be practiced to improve the Physics Class 11 skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
______________ implies that things cannot start, stop, or change direction all by themselves.
A. third law of motion
B. second law of motion
C. first law of motion
D. None of the above
View Answer
Ans : C
Explanation: The first law of motion implies that things cannot start, stop, or change direction all by themselves. It requires some force from the outside to cause such a change.
Question 2
Newton’s first law is also known as the law of inertia.
A. TRUE
B. FALSE
C. Can be true or false
D. Can not say
View Answer
Ans : A
Explanation: True, This property of massive bodies to resist changes in their state of motion is called inertia. Newton’s first law is also known as the law of inertia.
Question 3
The second law of motion, force equal to?
A. product of its mass and time
B. product of its mass and velocity
C. product of its mass and displacement
D. product of its mass and acceleration
View Answer
Ans : D
Explanation: The 2nd law of motion states that the force acting on the body is equal to the product of its mass and acceleration.
Question 4
Which law of Newton helps in finding the force on a body?
A. First law
B. Second Law
C. Third Law
D. Fourth Law
View Answer
Ans : B
Explanation: The second law of motion states that the net force applied on a body is proportional to the rate of change of momentum. On further experimentation, it was found that the force applied on a body is equal to the rate of change of momentum.
Question 5
The second law of motion describes?
A. what happens to the body when it exerts a force on another body.
B. what happens to the massive body when acted upon by an external force.
C. Both A and B
D. None of the above
View Answer
Ans : B
Explanation: The second law of motion describes what happens to the massive body when acted upon by an external force.
Question 6
What causes the motion of a body which is initially in the state of rest?
A. Force
B. Displacement
C. Speed
D. Velocity
View Answer
Ans : A
Explanation: The first law of motion states that a body remains in the state of motion or in the state of rest until and unless an external force is applied on it. Hence, the answer is force. This is also known as the law of inertia.
Question 7
What is the force applied on a body with 5 kg of mass and an acceleration of 7 m/s2?
A. 5 N
B. 20 N
C. 35 N
D. 70 N
View Answer
Ans : C
Explanation: According to the second law of motion, the force on a body is equal to the rate change of its momentum. On simplifying we get, F = ma. Therefore, Force = 5 x 7 = 35 N.
Question 8
The forces involved in Newton’s third law act ____
A. On the same object
B. On different objects
C. In same direction
D. On five bodies
View Answer
Ans : B
Explanation: The two forces involved in Newton’s third law are the cause force and the reaction force. The cause force acts on the contact surface or the contact body by the parent body. Whereas the reaction force acts on the parent body by the contact body.
Question 9
The second law of motion, in mathematical form can be written as ____
A. F = ma
B. F = v(dm/dt)
C. F = mv
D. F = dp/dt
View Answer
Ans : D
Explanation: The second law of motion states that the net force applied on a body is equal to the rate of change of momentum. Momentum is usually represented by ‘p’. Hence, the answer is F = dp/dt.
Question 10
Newton’s third law of motion implies the conservation of momentum.
A. Yes
B. No
C. Can be yes or no
D. Can not say
View Answer
Ans : A
Explanation: Yes, Newton’s third law of motion implies the conservation of momentum.