Two synchronized microwave sources, A and B, are emitting waves of wavelength 4.0 cm. Source A is located on the x-axis at x = 0, source B can be moved along the x-axis, and a microwave receiver is fixed on the x-axis at x = 82 cm. For each of the following positions of source B determine whether the waves from the sources will reach the receiver in phase (constructive interference), out of phase (destructive interference), or with a phase difference of π/2 rad.
a) x = -8 cm
b) x = -6 cm
c) x = -5 cm
d) x = -4 cm
e) x = -3 cm
f) x = -2 cm

report!

explanation:

physics means: "the branch of science concerned with the nature and properties of matter and energy. the subject matter of physics, distinguished from that of chemistry and biology, includes mechanics, heat, light and other radiation, sound, electricity, magnetism, and the structure of atoms."

russian is not my first language, so i'm afraid i can't write out an answer in russian, but hopefully you can find a way to do so. here's my best translation of the problem: you're given a plot of a particle's position in one-dimensional space over time, and you're asked to find either the total distance traveled by the particle after 6 seconds had elapsed, or the total displacement of the particle after 6 seconds.

if you want the total distance traveled, you would first need to determine the particle's velocity as a function of time, then integrate that over the 6-second interval. we know the position function is quadratic with roots at 0 and 6, so we have

where is unknown. because the position is parabolic, there is symmetry about the midpoint at , and we know that

so that the position function is

which means the velocity is

then the total distance traveled is

so the total distance traveled is 20 m.

on the other hand, if you want to find displacement: the particle starts at and ends at , so its displacement is 0.