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Question
Two wires A and B, having identical geometrical construction, are stretched from their natural length by small but equal amount. The Young modules of the wires are YA and YB whereas the densities are \[\rho_A \text{ and } \rho_B\]. It is given that YA > YB and \[\rho_A > \rho_B\]. A transverse signal started at one end takes a time t1 to reach the other end for A and t2 for B.
Options
t1 < t2
t1 = t2
t1 > t2
the information is insufficient to find the relation between t1 and t2.
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Solution
the information is insufficient to find the relation between t1 and t2.
\[v = \sqrt{\frac{\eta}{\rho}}\]
But because the length of wires A and B is not known, the relation between A and B cannot be determined.
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