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Microwaves from a transmitter are direct...

Microwaves from a transmitter are directed toward a plane reflector. A detector moves along the normal to the reflector. Between positions of 14 successive maxima, the detector travels distancee of 0.14 m . What is the frequency of transimitter?

A

`1.5 xx 10^(10) Hz`

B

`10^(10) Hz`

C

`3 xx 10^(10) Hz`

D

`6 xx 10^(10) Hz`

Text Solution

Verified by Experts

The correct Answer is:
a
The detector receives direct as well as reflected waves. The distance moved between two consecutive position of maxima is `lambda//2`.
`14 xx (lambda)/(2) = 71 = 0.14 m`
`implies lambda = 0.02 m`
`c = n lambda`
Putting `c = 3 xx 10^(8) m//s`, we have
`n = (c)/(lambda) = (3 xx 10^(8))/(0.02) = 1.5 xx 10^(10) Hz`.
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