That is a lunar eclipse. At night, when the Earth is between the Sun and the moon, the moon would appear to be red. Just for future reference, a solar eclipse is when the Moon is between the Sun and Earth. Speaking of which, check out the solar eclipse this August!
A compound machine is a combination of at least two simple machines. Simple machines can be a lever, a wedge, a while + axle, an incline plane, a pulley, and a screw.
There are many examples of compound machines. One of them is a showel that combines a wedge (the scoop part of shovel) and a lever (the handle to transfer the force to lift).
A much more complex compound machine is a bicycle, comprising simple machines ranging from wheels and axles, to screws, and levers (think of the pedals).
speed=frequency*wavelength, so frequency=speed/wavelength. frequency=80*0.2
Frequency = 16 Hz
Answer:
Explanation:
We shall apply the formula of Doppler effect here
F( APPARENT) = F( REAL ) X V/(V + Vs) [ v is velocity of sound and Vs is velocity of source.
415 = 440 X 343/343+Vs
142345 + 415Vs = 150920
415 V₀ = 8575
V₀ = 20.66 m/s.