Police radars determine speed by measuring the Doppler shift of radio waves reflected by a moving vehicle. They do so by determi
1 answer:
Answer: 0.81 GHz
Explanation:As written in the question police radars works by determining the beat frequency between sent and reflected wave. This beat frequency is just difference of the frequencies of the sent and reflected wave.
To Calibrate the Radar the turning fork must produce the beat frequency similar to that produce by reflected wave at right speed which in this case is 55mph
Hence we know that turning fork frequency=Δf
Δf=f'-f
here f=10.5 Ghz
f=10.5 *10^9
f=10500000000
also
v_s=55mph
v_s=24.5872 m/s
since the source is moving a/c to doppler effect
taking speed of sound to be v=344m/s
f'=11.3*10^9
Δf=8.08*10^8
Δf=0.81 GHz
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Explanation:
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Answer:
V = 4.859[m^3]
Explanation:
In order to solve this problem, we must find the mass of the refrigerant, as there are no leaks or leaks of refrigerant, we can conclude that the mass is conserved throughout the process.
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