Question

A string of length 0.4 m and mass 10^–2 kg is clamped at its ends. The tension in the string is 1.6 N. When a pulse travels along the string, the shape of the string is found to be the same at times t and t + Dt. The value of Dt is –

• A. 0.05 sec
• B. 0.1 sec
• C. 0.2 sec
• D. 0.4 sec

Answer 1

Answer: (B)

0.1 sec

Answer 2

v = $\sqrt{\frac{T}{\mu}}$ = $\sqrt{\frac{1.6 \times 0.4}{10^{–2}}}$ = 8 m/s

S = vt = 0.8 = 8 Dt Ž Dt = 0.1 sec