Q.
Equation of a progressive wave is given by y=0.2cosπ(0.04t+0.02x−6π). The distance is expressed in cm and time in second. What will be the minimum distance between two particles having the phase difference of 2π ?
Comparing with y = a cos (ωt+kx−ϕ)
We get, k=λ2π=0.02π ⇒λ=100km
Also, it is given that phase difference between particles Δϕ=2π.
Hence, path difference between them Δx=2πλ×Δϕ =2πλ×2π =4λ=4100 =25cm