Who Figured This Out? The American astronomer Edwin Hubble made the observations in 1925 and was the first to prove that the universe is expanding. He proved that there is a direct relationship between the speeds of distant galaxies and their distances from Earth. This is now known as Hubble's Law.
A billiard ball. unless hit, the balls stay at rest. however when hit into another, the balls do not stop unless acted upon by another force.
Answer:
Explanation:
wavelength, λ = 3.4 m
wavelength, λ' = 3.3 m
Speed, v = 340 m/s
f = v / λ = 340 / 3.4 = 100 Hz
f' = v / λ' = 340 / 3.3 = 103.03 Hz
Frequency of beat, n = f' - f = 103.03 - 100 = 3.03 Hz