Two cars move in the same direction along a road: A at 20 m s -1 and B at 15 m s -1 , with B 100 m ahead of A. The time for A to catch up with B is:

⚛️ Physics · Motion in a Straight Line · NEET & JEE

Two cars move in the same direction along a road: A at 20 m s-1 and B at 15 m s-1, with B 100 m ahead of A. The time for A to catch up with B is:

Answer: 20 s.

A 10 s
B 30 s
C 25 s
D 20 s

Correct answer: D. 20 s

Explanation: Relative speed of A with respect to B = 20 - 15 = 5 m s-1. Time = gap / relative speed = 100 / 5 = 20 s.

On a velocity-time graph for uniform acceleration, the slope of the line gives the acceleration and the shaded area under the line gives the displacement.

Concept context

Equations of motion, projectile motion, relative velocity. Foundation of all mechanics.

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Two cars move in the same direction along a road: A at 20 m s<sup>-1</sup> and B at 15 m s<sup>-1</sup>, with B 100 m ahead of A. The time for A to catch up with B is:

Concept context

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