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 :)

Jet streams are relatively narrow bands of strong wind in the upper levels of the atmosphere. the winds blow from west to east in jet streams but the flow often shifts to the north and south. jet streams follow the boundaries between hot and cold air. the earth's rotation is responsible for the jet stream as well.

10 is the . . .

Is a  vector quantity  that refers to "the rate at which an object changes its position." imagine a person moving rapidly - one step forward and one step back - always returning to the original starting position. while this might result in a frenzy of activity, it would result in a zero velocity. because the person always returns to the original position, the motion would never result in a change in position. since velocity is defined as the rate at which the position changes, this motion results in zero velocity. if a person in motion wishes to maximize their velocity, then that person must make every effort to maximize the amount that they are displaced from their original position. every step must go into moving that person further from where he or she started. for certain, the person should never change directions and begin to return to the starting position.