Using a radar gun, you emit radar waves at a frequency of 6.2 ghz that bounce off of a moving tennis ball and recombine with the original waves. this produces a beat frequency of 969 hz. how fast was the tennis ball moving?

23.4 m/s

Explanation:

f = actual frequency of the wave = 6.2 x 10⁹ Hz

= frequency observed as the ball approach the radar

= frequency observed as the ball recede away from the radar

V = speed of light

= speed of ball

B = beat frequency = 969 Hz

frequency observed as the ball approach the radar is given as

                                eq-1

frequency observed as the ball recede the radar is given as

                                 eq-2

Beat frequency is given as

Using eq-2 and eq-1

inserting the values

= 23.4 m/s

it doesn't. it was imagined up in the middle ages.