a. Explain what is meant by:
i. A coherent source of waves.
ii. Phase difference.
b. A student, experimenting with microwaves, sets up the arrangement shown in this diagram.

With the metal plate at position A there is a very small signal. He slowly moves the plate back, leaving the receiver in the same position. As he does so, he finds that the intensity initially rises until it becomes a maximum, then falls back to a minimum. This cycle repeats a total of five times until the plate reaches position B, where once again there is a minimum.
i. Explain why a series of maxima and minima are heard.
ii. Determine the frequency of the microwaves.
c. Explain why there was a minimum when the plate was at position A, next to the detector.

Transcribed Image Text:

microwave microwave metal transmitter receiver plate 42.0 cm A Figure 14.22