Given, wave equation, y=0.002cos(300t−15x)
Mass density, μ=0.1kg/m
Comparing the given wave equation with y=acos(ωt−kx), we have ω=300rads−1,k=15radm−1 ∴ Velocity of wave, v=kω=15300=20m/s
Wave speed in string is also given by v=μT
where, T= tension in the string and μ= mass per unit length of string.
Substituting the values in Eq. (i), we get 20=0.1T⇒400=0.1T ⇒T=40N