Question

Which of the following person is in an inertial frame of reference?

• A. A pilot in an aeroplane which is taking off.
• B. A driver driving a bus which is moving with constant velocity.
• C. A child revolving in a merry - go - round.
• D. A man in a train which is slowing down to stop.

Hint:

An inertial frame moves with constant velocity; accelerating frames are non-inertial.

Answer 1

The Correct Option is B

Step 1: Test:
Ask whether the frame has any acceleration, whether in speed or direction.

Step 2: Apply:
Take-off: speed changes. Merry-go-round: direction changes. Slowing train: speed changes. Constant-velocity bus: neither changes.

Step 3: Answer:
Option (B).

Final Answer:
Option (B). \[ \boxed{\text{(B)}} \]