L = (n/2)lambda
lambda = 2L/5 = 2*10/5 = 4
v = lambda*f
v = 4 * 1.5 = 6 m/s
Two kids sitting on opposite sides of a small lake use sticks to beat the surface of the
water at a frequency f=1.5 Hz. They notice that a standing wave pattern develops between
the points where they are disturbing the water surface. They count n=5 nodes over the
L=10 m distance between them.
a) What can be said about the speed of wave propagation on the water surface based on
this information.
1 answer