Question 485: Waves

Question

The fundamental frequency of a closed organ pipe of length 20 cm is equal to the second overtone of an organ pipe open at both the ends. The length of organ pipe open at both the ends is

Accepted Answer

Fundamental frequency of closed organ pipe
$${V_c} = {V \over {4{l_c}}}$$
Fundamental frequency of open organ pipe
$${V_0} = {V \over {2{l_0}}}$$
Second overtone frequency of open organ pipe
$$ = {{3V} \over {2{l_0}}}$$
$${V \over {4{l_c}}} = {{3V} \over {2{l_0}}}$$
$$ \Rightarrow {l_0} = 6{l_c} = 6 	imes 20 = 120$$ cm

Answer

120 cm

Answer

140 cm

Answer

80 cm

Answer

100 cm

Waves

The fundamental frequency of a closed organ pipe of length 20 cm is equal to the second overtone of an organ pipe open at both the ends. The length of organ pipe open at both the ends is

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