Two sinusoidal waves with identical wavelengths and amplitudes travel in opposite directions along a string with a speed of 10 cm/s. If the time interval between instants when the string is flat is 0.50 s, what is the wavelength of the waves?
v = w/k = lamda * frequency
The Attempt at a Solution
The solution gives T/2 = 0.50 and T = 1 s
Why do we have to multiple by two? In fact, if I didn't take twice the given time, i would have this
frequency = 1/T = 0.5 still which doesn't make sense...
How does "time interval between instants" implies twices? I know between is used when comparing two things. But I just thought that 0.5 was the time the string stayed flat.
Thank you very much.