Question

A taut string for which µ = 5 × 10^–2 kg/m is under tension of 80 N. How much is the average rate of transport of potential energy if the frequency is 60Hz and amplitude is 6 cm

(Given 4p² = 39.5)

• A. 52W
• B. 256 W
• C. 512 W
• D. 215 W

Answer 1

Answer: (B)

256 W

Answer 2

Average power  ≅ P_av = $\frac{1}{2}$mvw²A²

Average rate of transport potential energy

= $\left( \frac{dU}{dt} \right)$ = $\frac{P_{av}}{2}$ = $\frac{1}{4}$ mvw²A²

= 256 W