Suppose atoms at rest emit visible light with a wavelength of 500 nm. At what wavelength would the light from the atoms be observed if the atoms were moving toward the earth at a speed of 20,000 km/s?
2007-09-21 03:21:45 · 3 answers · asked by New Mommy 1 in Science & Mathematics ➔ Physics
I got 468nm, using the guys equation from above. It makes more sense. They show the equation at the following website.
c = 3.8 X10^8m/s
v= 20,000 X10^3m/s
λ_e = 500 X 10^-9 m
2007-09-21 04:37:59 · answer #1 · answered by vcas30 3 · 1⤊ 1⤋
The wavelength would decrease due to the Doppler effect. The formula is:
λ_o = λ_e · sqrt((1-v/c)/(1+v/c))
where λ_e is the emitted wavelength, and λ_o is the observed wavelength, and v is the speed of approach.
2007-09-21 11:32:03 · answer #2 · answered by RickB 7 · 2⤊ 1⤋
i dont know if what i am saying is right. but i guessed this. atoms at rest cannot emit light continuously unless they r getting excited continuously. ie. emission of photons will not take place once they are de-excited. even when they r moving at high speeds, without getting energized at the atom level, they wont emit light.
2007-09-21 11:42:32 · answer #3 · answered by newtonian 2 · 0⤊ 1⤋