Answer:
Let L be the length of the wire.
N λ = M L where N is the number of wavelengths λ. Also, M and are integers and L is the length of the wire
There must be nodes at the ends of the wire and anti-nodes at the points of zero displacement - λ/2, λ, 3λ/ 2, etc.
The simplest would be 2 λ = L or L = λ / 2
In such a situation one would have
N-A-N or node-antinode-node
There is a 180 degree phase change upon reflection of the wave creating the standing wave
The distance between nodes or anti-nodes must be λ/2 and there must be nodes at the ends of the wire
