問題詳情
40. A car approaches a stationary police car at 36 m/s. The frequency of the siren (relative to the police car) is 500 Hz. What is thefrequency (in Hz) heard by an observer in the moving car as he approaches the police car? (Assume the velocity of sound in airis 343 m/s.)
(A) 220
(B) 383
(C) 448
(D) 526
(E) 552
參考答案
答案：E
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)