First law of motion(lec 2)

 video lectures for the First law of motion

Question 1: A change in the state of rest or of uniform motion is produced by _____.

a) Energy

b) Momentum

c) Acceleration 

d) Force

Question 2: A car at rest can be moved or a moving car can be stopped by applying ______.

a)  external work

b) external force

c) energy

d) none of the above

Question 3: When a person is walking on ground 

(a) he applies a force on the ground. 

(b) the ground exerts a force on him. 

(c) No force is applied by the person. 

(d) Both (a) and (b)

Question 4: A person getting down from a fast-moving bus falls on the ground. This can be explained by _____.

Question 5: Define inertia of motion.

Question 6: Define inertia of direction.

Question 7: Discuss with an example to show that inertia depends on mass.

Question 8: State Newton’s first Laws of motion.

Question 9. When the branch of a tree is shaken, the ripe fruits

get detached from the branch. This is an example of

(a)  Newton’s first law of motion.

(b)  Newton’s second law of motion.

(c)  Newton’s third law of motion.

(d)  All the above

Question 10. When a person is walking on ground

(a) he applies a force on the ground.

(b) the ground exerts a force on him.

(c) No force is applied by the person.

(d) Both (a) and (b)

Answer Key

Q1.  (d),  Q2.  (b),  Q3.  (d)

Q4.  A getting passenger getting down from a moving bus, falls in the direction of the motion of the bus. This is because his feet come to rest on touching the ground and the remaining body continues to move due to inertia of motion.

Q5.  Inertia is defined as a property of matter by which it remains at the state of rest or in uniform motion in the same straight line unless acted upon by some external force.

Q6.   Inertia of direction is defined as a body's ability to resist changes in its motion direction.

Q7.  The plastic ball, being lighter, will have far less resistance in moving from its state of rest to motion, whereas the metal ball will be harder to move.

Q8.   An object at rest remains at rest, and an object in motion remains in motion at a constant speed and in a straight line unless acted on by an unbalanced force. 

Q9.  (a),  Q10.  (d)