When is acceleration considered positive?
Show answer & explanation
Correct answer: C
Explanation
Correct Answer:-
When it is in the direction of velocity.
Explanation:-
Acceleration is considered positive when it acts in the same direction as the object's velocity. This simply means that the object's velocity is increasing over time. If acceleration acts opposite to the direction of velocity, the velocity begins to decrease; this is known as 'retardation' (or deceleration) and is considered negative acceleration.
Key Points:-
Formula for acceleration: a = (v - u) / t (where v is final velocity, u is initial velocity, and t is time).
If the final velocity is greater than the initial velocity (v > u), the acceleration will be positive.
If the velocity is constant (not changing), the acceleration will be zero.
Important Questions and Answers:
Question: If a vehicle comes to a stop after applying brakes, what will be the nature of the acceleration?
Answer: The acceleration will be negative because the velocity is decreasing.
Question: What is the S.I. unit of acceleration?
Answer: Meter per second squared (m/s²).