A police officer standing at the side of the road uses a radar emitting frequency of 24.15 GHz. A car is going away from the officer at a speed of 50mph. What will be the difference in frequency of the beam reflected by the car received back by the radar? a. 4.0 kHz (lower frequency)
b. 1.8 kHz (higher frequency)
c. 4.0 kHz (higher frequency)
d. 1.8 kHz (lower frequency)

The correct answer is  C

Explanation:

  From the question we are told that  

       The frequency of the radar is

         The speed of the car is

Generally the difference frequency reflected by the car and the frequency which the radar receives back is mathematically represented as

Here  c is the speed of light with value  

=>          

=>    

=>      

Given that the value is positive then it a higher frequency

would be false hope this out

a

explanation:

no diagram was provided, but i'm guessing it's the one i've attached to my answer.

here, a mechanical force turns the rod.   this generates an electric current in the coil, which powers the bulb.