1. Two ropes are tied together. The first has a linear
density of µ1 = 3.0 x 10-4 kg/m and the second has µ2 = 1.2 x 10-4
kg/m. They are under a common tension of 700 N.
(a) What are the speeds of waves in the two strings?
(b) A pulse is started in the first string as shown. Draw the reflected and
transmitted pulses in the two parts of the string.
2. I have two waves in a string. One of them is given below, where x is
in cm and t is in seconds.
Write the function for a wave that
(a) Will produce destructive interference with the first wave.
(b) Travels the same direction but is 120° out of phase with the first.
(c) Has the same wavelength but travels three times faster than the first.
(d) Produces standing waves when added to the first wave.
3. A sinusoidal wave is established in a string. The amplitude of the wave
is 0.12 cm, the string is under 150 N tension, the wave speed is 180 m/s, and
the wavelength is 2.5 m.
(a) Write a function for this wave.
(b) Rewrite equation 17-31 in terms of tension rather than wavespeed.
Eq. 17-31, p. 382 
where ym = Y = amplitude of wave.
(c) What is the average power carried by the wave?
(d) I now double the tension in the string, but leave it connected to the same
source. What happens to the following
(i) wave speed, (ii) frequency, (iii) wavelength, (iv) average
power.
(Your answers should be like the following "Increases by 4 x, stays the
same, decreases by a factor of 2 squared," etc.)
4. Write out solutions to #4. CLPhys1 17.P.037 A string oscillates
from WebAssign PS 5.0 waves043.
This page maintained by Anne G. Young. Last modified 08-Apr-2005 .