A sinusoidal wave travels along a string with linear density 0.02 kg/m, amplitude 0.02 m, angular frequency 100 rad/s and wave speed 50 m/s. If its average power is N watts, find N.
Physics · Wave Motion · question based on string wave
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Question

A sinusoidal wave travels along a string with linear density 0.02 kg/m, amplitude 0.02 m, angular frequency 100 rad/s and wave speed 50 m/s. If its average power is N watts, find N.

G1 Physics · Accepted Answer

Average power is P̄ = ½μω²A²v. Substitute μ = 0.02, ω = 100, A = 0.02, v = 50. Thus, P̄ = ½(0.02)(100²)(0.02²)(50). Now, 100² = 10000, 0.02² = 4×10⁻⁴. Hence, P̄ = 0.01×10000×4×10⁻⁴×50 = 2 W. Therefore, N = 2.