Question 99: Waves

Question

A wire of length 30 cm, stretched between rigid supports, has it's nth and (n + 1)th harmonics at 400 Hz and 450 Hz, respectively. If tension in the string is 2700 N, it's linear mass density is ____________ kg/m.

Accepted Answer

$${v \over {2l}} = 50$$ Hz
$$ \Rightarrow T = {\left[ {100 	imes \left( {{{30} \over {100}}} ight)} ight]^2} 	imes \mu $$
$$ \Rightarrow \mu  = {{2700} \over {900}} = 3$$

Waves

A wire of length 30 cm, stretched between rigid supports, has it's nth and (n + 1)th harmonics at 400 Hz and 450 Hz, respectively. If tension in the string is 2700 N, it's linear mass density is ____________ kg/m.

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