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 government has declared that a hurricane is likely to hit the east coast. which government division is part of acf and provides guidance to citizens? a. job opportunities for low-income individuals b. office of human services emergency preparedness and response c. assets for independence d. low-income home energy assistance program

If two students are running down the hall toward each other, trying to get to class, and they have the same mass and acceleration, what will happen when they collide? will their forces cancel out or will each one experience a reaction?

Abird flies directly overhead from where you stand at an altitude of 300.0 m and at a speed horizontal to the ground of 20.0 m/s. the bird has a mass of 2.0 kg. the radius vector to the bird makes an angle \thetaθ with respect to the ground. the radius vector to the bird and its momentum vector lie in the xyxy-plane. what is the bird’s angular momentum about the point where you are standing?