A thin steel cable with 2.0 mm diameter is hooked up to a vibrating device, which exerts a tension of 8.5 N on the cable. The device vibrates at a frequency of 70.0 Hz, producing waves in the cable with an amplitude of 0.50 cm. Calculate the power output of this device, assuming the waves do not reflect back along the cable. (The density of steel is ρ_steel=7800 kg/m³).

A guitar string is plucked and vibrates with a tension of 180 N. The string has a linear density of 0.050 kg/m. What power value is required to sustain a 440-Hz musical tone if the amplitude of the string’s vibration is 1.2 cm? Hint use: $\bar{P}=2 \pi^{2} \mu v f^{2} A^{2}$

Calculate the average power of ocean waves acting against a small boat anchored near the shore. The waves have an amplitude of 0.40 m, a wavelength of 5.0 m, and a period of 6.0 s.