Vibrating a long spring with a succession of pulses with a frequency of 50hz produces adjecent nodes that are separated by 3.5cm. What is the velocity of the longitudinal waves formed?

Answer 1

f*lambda=v
nodes are at successive half wavelengths...
f*7.0cm=speed
solve for speed, f=50 hz

Answer 2

velocity = lamda * fequency
v= (.035)*(50)
v= 1.75 m/s