英文物理题,求解.On a cello, like most other stringed instruments, t

问题描述:

英文物理题,求解.
On a cello, like most other stringed instruments, the positioning of the fingers by the player determines the fundamental frequencies of the strings. Suppose that one of the strings on a cello is tuned to play a middle C (262 Hz) when played at its full length. By what fraction must that string be shortened in order to play a note that is the interval of a third higher (namely, an E (330 Hz))?, How about a fifth higher or a G (392 Hz)?
1个回答 分类:英语 2014-09-17

问题解答:

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在一个大提琴,像大多数其他弦乐器,该演奏者的手指定位决定了弦的基本频率.假设对大提琴的琴弦之一被调整到在其全长振动时发出中央C(262赫兹).怎样缩短该弦振动部分的分数,以便发出第三级的音(即一个E(330赫兹))?第五级的音或一个G(392赫兹)?
根据弦上的驻波理论,设全弦长为L0,基音频率为f0
L/L0=F0/F
发出第三级的E音L/L0=F0/F=262/330=4/5 即按在约4/5处
发出第五级的G音L/L0=F0/F=262/392=0.68 即按在约7/10处
 
 
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