Question

If vibrations of a string are to be increased by a factor of two, then tension in

the string must be made

[AIIMS 1999; Pb. PET 2000]

• A. Half
• B. Twice
• C. Four times
• D. Eight times

Answer 1

The correct option is C

Four times

$n\propto \sqrt{T}$
$\frac{n_1}{T_1}=\frac{n_2}{T_2}$
$\sqrt{T_2}=\frac{n_2\sqrt{T_1}}{n_1}\Rightarrow \sqrt{T_2}=2\sqrt{T_1}$
$T_2=4T_1$