Two long strings A and B, each having linear mass density 12 × 10−2 kg m−1, are stretched by different tensions 48 N and 75 N respectively and are kept parallel to each other with their left ends at x = 0. Wave pulses are produced on the strings at the left ends at t = 0 on string A and at t = 20 ms on string B. When and where will the pulse on B overtake that on A?
At t = 100 ms at x = 20 m
Suppose v and v’ are wave speeds in string A and B respectively.
At the time, wave starts travelling in string B, A wave has travelled,
So, Relative Speed between A and B is 5m m/s.
So, time taken to overtake is,