A 4.0 kg block is suspended from the ceiling of an elevator through a string having a linear mass desity of `19.2xx10^-3 kgm^-1`. Find the speed (with respect to the string) with which a wave pulse can proceed on the string if the elavator accelerates up at the rate of `2.0ms^-2. Take g=10 ms^-2`.

Explanation

As elevator accelerates up at `2 m/s^(2)` tension in the string is
`T = m(g+a)`
= 4(10+2) = 48 N
Linear mass density of string is
`mu = 19.2 xx 10^(-3)` kg/m
Speed of transverse waves on string is
`v = sqrt((T)/(mu))`
`sqrt((48)/(19.2 xx 10^(-3)))`
= 50 m/s