Question

Two particles having the same phase must be at

• A. a crest and a trough respectively at the same time
• B. a crest and at the mean position respectively at the same time
• C. a trough and at the mean position respectively at the same time
• D. Two consecutive crests respectively at the same time

Answer 1

The correct option is D Two consecutive crests respectively at the same time

For same phase angle, the two consecutive crest of wave 1 and wave 2 should be occurring at the same time period i.e. when they are in the same phase.Also same phase implies same frequency as well as same wavelength which will happen only if $A_B=A_D$ and $A_A=A_C$