Question

Which statement describes completely "a body at rest"?

• A. when a body does not change its position with time
• B. when a body does not change its position with respect to the surroundings
• C. when a body does not change its position with respect to the time and surroundings
• D. none of the above.

Answer 1

The correct option is C

when a body does not change its position with respect to the time and surroundings

1. In the above definition, surroundings mean one or more stationary objects around the given body.
2. These stationary objects can be called reference points.
3. For example, if a chair is placed in the middle of a room, then the walls of the room are its surroundings.
4. If the position of the chair (i.e., its distances from the walls) does not change with respect to the walls as well as time, then the chair is at rest.

Hence, option (C) “when a body does not change its position with respect to the time and surroundings” is the correct answer.