COMEDK · Physics · 7. Center of Mass Momentum and Collision
If the surface is a perfect reflector, then the change in momentum of the wave after falling on the surface is
- A \(p\)
- B \(2 p\)
- C \(\frac{p}{2}\)
- D \(-2 p\)
Answer & Solution
Correct Answer
(D) \(-2 p\)
Step-by-step Solution
Detailed explanation
\(p\) is the momentum of incident wave. \(\therefore\) Momentum of reflected wave after reflecting from perfect reflector \(=-p\) \(\therefore\) Change in momentum \(=\) Final momentum - Initial momentum \[ =-p-p=-2 p \]
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