Answer:
0.30m
Explanation:
When two pulses present interference, we say that the interference is destructive interference when the maximum of one of the pulse coincides with the minimum of the other pulse (or with the maximum in a opposite direction). For this problem he have two cases
1. It will be destructive interference if the reflected pule has its maximum in a opposite direction in comparison with the other pulse (this happens when the density of the post is higher that the density of the string, that is the most possible). The amplitude will be
[tex]A-A_{r}=0.15m-0.15m=0m[/tex]
2. It will be constructive interference if both maximums coincide in direction
[tex]A+A_{r}=0.15m+0.15m=0.30m[/tex]
I hope this is usefull for you
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