本题目来源于试卷: Physics Unit12: Sound，类别为 通用国际物理
[单选题]
At a distance of 15 m from h0gjrr0ca;r* a sound source the intensity levelk np)lsti +m(z 9fh)5a is 60 dB. What is the intensity level (in dB) at a point 2.0 m from the sourc nsi 5zthl))km9(+pafe? Assume that the source radiates equally in all directions.
A. $55.7 \; dB$
B. $57.5 \; dB$
C. $75.5 \; dB$
D. $77.5 \; dB$
参考答案: D
本题详细解析:
暂无
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