KEAM 2017 Physics and Chemistry Paper

The speed of radio waves is equal to electromagnetic wave speed i.e.3108m/s
Given, the distance of radio station, s=200km
=200×103m
Time taken by radio wave to his toner
t=‌

s

c

=‌

200×103

3×108

=666×10−6
=666µs
The wave emitted send out per second =972kHz
=972×103Hz
=9.72×105 crest per second