Question

plzzz solve this question .........

Answer 1

Planck’s quantum theory = Based on the assumption that all atoms on the surface of the heated solid vibrate at the frequency, Planck developed a model that came to be known as Planck’s equation. Through experiments of frequencies and temperature, Planck was able to generate a constant, Planck’s constant

                                                           h = 6.62607 x 10-34 J s 

Using this constant he was able to restate his theory: energy was directly proportional to frequency. He wrote his equation as 

                                                          E=hν

where E is energy, h is Planck’s constant, and v is frequency.

(i) Energy (E) of a photon is given by the expression,

E=hν

Where, h = Planck’s constant = 6.626 × 10–34 Js

ν = frequency of light = 3 × 1015 Hz

Substituting the values in the given expression E = hv we get

E = (6.626 × 10–34) (3 × 1015)

E = 1.988 × 10–18 J

 

(ii) Energy (E) of a photon having wavelength (λ) is given by the expression,

 where , h = Planck’s constant = 6.626 × 10–34 Js

c = velocity of light in vacuum = 3 × 108 m/s

Substituting the values in the given expression of E: