Correct answer choice is:
D. A frequency higher than the original frequency.
Explanation:
This is a true case of Doppler's effect. The Doppler effect can be defined as the effect originated by a traveling source of waves in which there is a visible higher variation in pulse for observers towards what the source is progressing and a visible descending shift in rate for observers from what the source is dropping.
Answer:
2.52 m/s
Explanation:
When the man takes a step, his foot is stationary while his body revolves around it. At the point when his body is directly above his foot, there will be no normal force at his maximum speed.
Sum of the forces in the radial direction:
∑F = ma
mg = m v² / r
g = v² / r
v = √(gr)
Given that r = 0.650 m:
v = √(9.8 m/s² × 0.650 m)
v = 2.52 m/s
To solve the exercise it is necessary to take into account the concepts of wavelength as a function of speed.
From the definition we know that the wavelength is described under the equation,
![\lambda = \frac{c}{f}](https://tex.z-dn.net/?f=%5Clambda%20%3D%20%5Cfrac%7Bc%7D%7Bf%7D)
Where,
c = Speed of light (vacuum)
f = frequency
Our values are,
![f = 2Hz](https://tex.z-dn.net/?f=f%20%3D%202Hz)
![c = 3*10^8km/s](https://tex.z-dn.net/?f=c%20%3D%203%2A10%5E8km%2Fs)
Replacing we have,
![\lambda = \frac{c}{f}](https://tex.z-dn.net/?f=%5Clambda%20%3D%20%5Cfrac%7Bc%7D%7Bf%7D)
![\lambda = \frac{3*10^8km/s}{2Hz}](https://tex.z-dn.net/?f=%5Clambda%20%3D%20%5Cfrac%7B3%2A10%5E8km%2Fs%7D%7B2Hz%7D)
![\lambda = 1.5*10^8m](https://tex.z-dn.net/?f=%5Clambda%20%3D%201.5%2A10%5E8m)
<em>Therefore the wavelength of this wave is
</em>