Question

Length of a string tied to two rigid supports is 40cm. Maximum length (wavelength in cm) of a stationary wave produced on it is?

(a) 20

(b) 80

(c) 40

(d) 120

The question was posed to me during an online interview.

The doubt is from Longitudinal Waves in section Waves of Engineering Physics I

Answer 1

Right option is (b) 80

For explanation I would say: When the string vibrates in one segment,

L=ʎ/2

ʎ=2L=2×40=80cm.