Question

The speed of a particle moving along a straight line increases as time passes and the acceleration is negative, then it means body is under deceleration.

• A. True
• B. False

Answer 1

The correct option is B False

Acceleration:

1. The rate of change of velocity with respect to time.
2. It is a vector quantity.

Deceleration:

1. Deceleration of a body whose velocity is decreasing with time.
2. For the deceleration of the body, the direction of velocity and acceleration is always opposite in direction.

When a particle moves along a straight line increases with time:

1. When acceleration is negative, velocity may be also negative and in this situation, the particle is accelerating in the negative direction, even though the acceleration is negative.
2. In this case, it is absolutely wrong to say negative acceleration means the body is under deceleration.

Hence, the given statement is false.