Answer:
Only option A is correct
Explanation:
From the concept of Doppler effect, only speed matters. Thus, the faster a vehicle is moving, the closer together the sound waves get compressed and the higher the frequency. For example, for a very fast vehicle traveling at the speed of sound; the compressions are all right on top of each other. Thus, faster speed means closer compressions and higher frequencies. Hence, option only option A must be true because X is a higher frequency and so it must be going faster. The distance to the person will affect the volume but will not the pitch so Option B is not correct. Option C too is not correct because It doesn’t matter whether you are speeding up or slowing down, it only matters who is going faster. For example, from option c concept, if truck X was going 10 m/h and speeding up while truck Y was going 50 mph and slowing down, it would not meet the requirement that X has a higher frequency because only actual speed matters, not what is happening to that speed. Thus only option A is the correct answer
The rotational speed of the person is 0.4 rad/s.
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Rotational speed (rad/s)</h3>
The rotational speed of the person in radian per second is calculated as follows;
v = ωr
where;
- v is linear speed in m/s
- r is radius in meters
- ω is speed in rad/s
ω = v/r
ω = 2/5
ω = 0.4 rad/s
Thus, the rotational speed of the person is 0.4 rad/s.
Learn more about rotational speed here: brainly.com/question/6860269
Answer:
Wavelength is 471 nm
Explanation:
Given that,
Lines per unit length of diffraction grating is 500 lines/mm.
The third maxima from the central maxima (m=3) is at an angle of 45°
We need to find the color of laser light shines through a diffraction grating.
The condition for maxima is :

d = 1/N, N = number of lines per mm

Explanation:
P =F * v
F = m * a = 65 kg * 9.81 ms^-2 * 12 passengers
v = d/t = 150m / 64 s
I think you can calculate and substitute this units should be watts
Good morning!
Excessive ventilation is harmful because it increases intrathoracic pressure, decreasing venous flow and causing problems in the conduction of heartbeats, since it changes the respiratory pattern. In addition, it can cause occasional problems such as reflux and regurgitation.
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