Radars are frequently used to identify distance and speed, such as how far away an object is or how fast it is moving. <span>The </span>radar<span> device can then use the change in frequency to </span>determine the speed<span> at which the </span>car<span> is moving. In laser-</span>speed<span> guns, waves of light are </span>used<span> in place of radio waves.</span>
Answer:
there is no motion for victor
a) 1.48 m/s
The tuning fork is moving by simple harmonic motion: so, the maximum speed of the tip of the prong is related to the frequency and the amplitude by

where
is the maximum speed
is the angular frequency
A is the amplitude
For the tuning fork in the problem, we have
, where f is the frequency
is the amplitude
Therefore, the maximum speed is

b) 
The fly's maximum kinetic energy is given by

where
is the mass of the fly
is the maximum speed
Substituting into the equation, we find

Answer:
4.6 kHz
Explanation:
The formula for the Doppler effect allows us to find the frequency of the reflected wave:

where
f is the original frequency of the sound
v is the speed of sound
vs is the speed of the wave source
In this problem, we have
f = 41.2 kHz
v = 330 m/s
vs = 33.0 m/s
Therefore, if we substitute in the equation we find the frequency of the reflected wave:

And the frequency of the beats is equal to the difference between the frequency of the reflected wave and the original frequency:
