Choose the correct option for the following Assertion (A) and Reason (R).

Question

G1 Physics · Accepted Answer

A moving source approaching a stationary wall produces a higher frequency at the wall: f₁ = f×v/(v−u). The stationary wall reflects this same frequency. The moving source then approaches the reflected wave and acts as a moving observer, giving another factor (v+u)/v. Therefore, fₑ = f×(v+u)/(v−u). Both Assertion and Reason are true, and the Reason correctly explains the Assertion. Correct option: A.