Physics/Honors Physics Lab
A system for generating standing transverse waves is shown below. (Basically there is a giant rectangle with a small oscillator on the top with a string attached and then a pulley on the side of the giant rectange with a mass hanging down on the other end) We are given frequency, length, mass. We are trying to find lambda. The only thing we are puzzled with is if the wave starts with a node or antinode because that would change the values for lambda.
Any point where the string is in contact with an surface that prevents the string from moving will be forced to be a node. Since the string is physically attached at each end, each end must be a node. In addition, since the smallest part of a standing wave that fits between two fixed points is 1/2 wavelength or any integer multiple thereof. Only multiples of 1/2 wavelength can form a standing wave on a string fixed at both ends. (In this context the pulley surface behaves as a fixed point.)