A wave's frequency is 2Hz and its wavelength is 4 m. What is the wave's speed?
1 answer:
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solution:
As Given plane is flying in east direction.
It throws back some supplies to designated target.
Time taken by the supply to reach the target =10 seconds
g = Acceleration due to gravity = - 9.8 m/s²[Taken negative as object is falling Downwards]
As we have to find distance from the ground to plane which is given by d.
d =
= meters
Distance from the ground where supplies has to be land to plane = Option B =490 meters
Answer:
The doppler effect equation is:
In the equation we have frequencies, but then we have the wavelengths of the lights, remember the relation:
v = f*λ
then:
f = v/λ
and v is the speed of light, then:
f = c/λ
where:
f' is the observed frequency, in this case, is equal to f = (3*10^17nm/s)/550 nm
f is the real frequency, in this case, is (3*10^17nm/s)/650 nm
vs is the speed of the source, in this case, the source is not moving, then vs = 0 m/s.
v is the speed of the wave, in this case, is equal to the speed of light, v = 3*10^8 m/s
v0 is your speed, this is what we want to find.
Replacing those quantities in the equation, we get:
(3*10^17nm/s)/550 = (3*10^8 m/s + v0)/(3*10^8 m/s)*(3*10^17nm/s)/650 nm
(650nm)/(550nm) = (3*10^8 m/s + v0)/(3*10^8 m/s)
1.182*(3*10^8 m/s) = (3*10^8 m/s + v0)
1.182*(3*10^8 m/s) - (3*10^8 m/s) = v0 = 54,600,000 m/s
So your speed was 54,600,000 m/s, which is a lot.