Part 1: A harmonic wave is traveling along a rope. It is observed that the oscil
ID: 1702930 • Letter: P
Question
Part 1:A harmonic wave is traveling along a rope. It is observed that the oscillator that generates the wave completes 39.0 vibrations in 25.0 s. Also, a given maximum travels 428 cm along the rope in 10.0 s. What is the wavelength?
__cm
Part 2:
Ocean waves are traveling to the east at 4.9 m/s with a distance of 18 m between crests.
(a) With what frequency do the waves hit the front of a boat when the boat is at anchor?
__Hz
(b) With what frequency do the waves hit the front of a boat when the boat is moving westward at 1.0 m/s?
__Hz
Explanation / Answer
The no.of vibrations n = 39 in 25s
then the no of vibrations in sec f = 39/25
= 1.56Hz
The speed of the wave v = 428cm/10 = 42.8cm/s
Now v = f
therefore the wavelength
= v/f = 42.8cm/s / 1.56
= 27.4 cm
(2) The speed of the waves v = 4.9m/s
the wavelength = 18m
therefore the frequency
f = v/ = 4.9/18 = 0.272 Hz
when the boat moving with v = 1m/s
then the relative speed v = 4.9+1 = 5.9m/s
therefore the frequency f =5.9/18 = 0.327 Hz