Waves
posted by Sivashen on .
a long fishing rod is kept upright .A boat engine causes the rod to vibrate.Mary speculates that the end of the rod moves to and fro 20 times in 1 minute.The amplitude of the vibrtion is 0.15m.Calculate the speed of the vibration at the end of the fishing rod

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Sra 
frequency f = 20 /60 = 1/3 Hz
x = .15 sin (2 pi (1/3) t)
v = .15(2 pi/3) cos (2 pi t/3)
= .1 pi cos (2 pi t/3)
or .1 pi maximum