Two wave pulses identical in shape but inverted with respect to each other are produced at the two ends of a stretched string. At an instant when the pulses reach the middle, the string becomes completely straight. What happens to the energy of the two pulses?
When two wave pulses of identical shape but inverted with respect to each other meet at any
instant, they form a destructive interference. The complete energy of the system at that instant
of interference, is stored in the form of potential energy within it. After passing each other, both
the pulses regain their original shape