A particle moves in a straight line with a retardation (SI units). Its speed is at . The time taken for the speed to fall to is
Answer and explanation
Correct answer: D.
- Step 1: Express deceleration as differential rate of velocity change: .
- Step 2: Separate variables and integrate from initial speed at to final speed at time : .
- Step 3: Evaluate the limits: .
Answer
.
Why not the others: assumes constant deceleration at the initial maximum value .
Practise more Kinematics.
Free questions with an explanation for every one, and full timed JEE Main mock tests.
More Kinematics questions
- A body starts with a velocity of and accelerates uniformly at . What is its velocity after (i…
- A body starts with a velocity of and accelerates uniformly at . What is its velocity after (i…
- A body starts with a velocity of and accelerates uniformly at . What is its velocity after (i…
- A body starts with a velocity of and accelerates uniformly at . What is its velocity after (i…
- A body starts with a velocity of and accelerates uniformly at . What is its velocity after (i…
- A body starts with a velocity of and accelerates uniformly at . What is its velocity after (i…