Question

There is head-on elastic collision between the two particles moving in the same direction with speeds \(5\text{ m/s}\) and \(3\text{ m/s}\) respectively. After collision, the velocity of the first particle becomes \(4\text{ m/s}\) in the same direction. The velocity of the second particle should be

• A. \(6\text{ m/s}\) in the same direction.
• B. \(4\text{ m/s}\) in the same direction.
• C. \(2\text{ m/s}\) in the opposite direction.
• D. \(3\text{ m/s}\) in the same direction.

Hint:

Relative velocity reverses in elastic collision.

Answer 1

The Correct Option is A

Concept:
For elastic collision: \[ v_1 - v_2 = -(u_1 - u_2) \] Step 1: Given values. \[ u_1 = 5, \quad u_2 = 3, \quad v_1 = 4 \]
Step 2: Apply relation. \[ 4 - v_2 = -(5 - 3) \] \[ 4 - v_2 = -2 \] \[ v_2 = 6 \text{ m/s} \]
Step 3: Conclusion. Velocity of second particle = \(6\text{ m/s}\)