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 :)

Acyclotron is used to produce a beam of high-energy deuterons that then collide with a target to produce radioactive isotopes for a medical procedure. deuterons are nuclei of deuterium, an isotope of hydrogen, consisting of one neutron and one proton, with total mass 3.34×10−27kg. the deuterons exit the cyclotron with a kinetic energy of 6.40 mev .a-what is the speed of the deuterons when they exit? b-if the magnetic field inside the cyclotron is 1.25 t, what is the diameter of the deuterons' largest orbit, just before they exit? c-if the beam current is 350 μa how many deuterons strike the target each second?