If the radio waves that are sent from the speed gun have a frequency of 400,000,002 Hz and the radio waves reflected off an approaching car have a frequency of 400,000,109 Hz, what is the speed of the car? (Hz is the SI unit of frequency, equal to cycles per second).

40.1 m/s or 144.36 km/h

Explanation:

The equation is (v=∆ f/f) x (c/2)

V is velocity

delta f is returned frequency minus intial frequency divided by the initial frequency

c is the speed of light in m/s divided by 2

v= (400,000,109 Hz - 400,000,002 Hz)/400,000,002Hz x (299,792,458 m/s)/2

explanation: magnetic pole, region at each end of a magnet where the external magnetic field is strongest. the south-seeking pole, or any pole similar to it, is called a south magnetic pole. unlike poles of different magnets attract each other; like poles repel each other.