Water waves of wavelength 4m are produced by two generators S1 and S2.

Each generation when operated by itself produces waves which have an amplitude A and P which is 3m from S1 and 5m from S2.

When the generator are operated in phase, what is the amplitude of oscillation at P?

A. 0

B.1/2A

C. A

D.2A

»»answer is A. I just need the reasoning :)

The scalar triple product computes the magnitude m of the moment of a force vector f about a specified line. it is m = (r × f) · n, where r is the position vector from the line to the point of application of the force and n is a unit vector in the direction of the line. use matlab to compute the magnitude m for the case where f = [12, −5, 4] n, r = [−3, 5, 2] m, and n = [6, 5, −7].