本题目来源于试卷: Physics Unit12: Sound，类别为 通用国际物理
[单选题]
The frequency of a train horn is 500 Hz. Assume thqy))cs ,i-dk 9igo: dwe speed of sound in air 9x itas)lrg5f yk9 b(-is 340 m/s. What is the frequency heard by an observer if the observksxl9rg ty )95(-bai fer is approaching the train with a speed of 30.0 m/s?
A. $456 \; Hz$
B. $500 \; Hz$
C. $544 \; Hz$
D. none of the above
参考答案: C
本题详细解析:
暂无
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