A youngster in a boat on a lake watches waves that seem to be an endless succession of identical
crests passing with a half-second interval between each. If every disturbance takes 1. 5 s to
sweep straight along the length of her 4. 5-m-long boat, what are the frequency, period, and
wavelength of the waves.
Solution
L =4.5 m t = 1.5 s T = 1/2 s f = 1 / T =2.0 Hz v = L/t = (4.5 m)/(1.5 s) = 3.0 m/s d=
v/f = (3.0 m/s)/(2.0 Hz) = 1.5 m
crests passing with a half-second interval between each. If every disturbance takes 1. 5 s to
sweep straight along the length of her 4. 5-m-long boat, what are the frequency, period, and
wavelength of the waves.
Solution
L =4.5 m t = 1.5 s T = 1/2 s f = 1 / T =2.0 Hz v = L/t = (4.5 m)/(1.5 s) = 3.0 m/s d=
v/f = (3.0 m/s)/(2.0 Hz) = 1.5 m
