wave interference

[MohsenKa]

Hello
Please excuse me if my English is not good!
I have a question:
Suppose that two pulse is traveling trough a string in opposite direction and with the same frequency and same amplitude, when the two pulse interference to each other , the amplitude will be 0 , and in this time there is no pulse in the string! where is the pulse's energy in this time?!
If it possible for you send me a simulation that shows this phenomenon.
Thanks a lot
Mohsen

[Fu-Kwun Hwang]

At the time when two wave cancel each other, the amplitude of two waves are all zero.
Howerer, the velocity at each point of the waves are not zero.
That is why you will see wave appear later on.
Please check out Superposition of pulses
The vertical displacement between blue and red curves are proportional to the velocity at each point.
Think about how wave is propagated!