Question

Neon gas is generally used in the sign boards. If it emits strongly at 616 nm.
calculate (a) the frequency of emission, (b) distance traveled by this radiation in
30 s (c) energy of quantum and (d) number of quanta present if it produces 2 J of
energy.​

Answer 1

Answer:

λ = 616nm  or = 616x10-9m

a) Frequency , v=c/ λ

                          = 3.8x108 / 616x10-9

                          = 4.87x1014 s-1

b) Velocity of the radiation = 3x108 m/s

Therefore distance travelled in 30s = 30x3x108 = 9.0x109m

c) E = hv

       = hc/ λ

       = (6.626x10-34)(3.0x108) / (616x10-9 )

       = 32.27x10-20J

d) No of quanta in 2J of energy = 2/32.27 x 10-28 = 6.2x1018