Question

the no. of photons of frequency 10^14 Hz in radiation of 6.62J will be

Answer 1

Energy of one photon , E = hν
where h is the plank's constant and ν is the frequency of photons
given, ν = 10¹⁴ Hz
h = 6.62 × 10⁻³⁴ Js

So, Energy of one photon, E = 6.62 × 10⁻³⁴ × 10¹⁴ = 6.62 × 10⁻²⁰ J

number of photons = given energy/energy of one photon
= 6.62 /6.62 × 10⁻²⁰ = 10²⁰

Hence, number of photons = 10²⁰

Answer 2

Energy Of Photon E=hν
Where h is Planck's constant =6.626176 x 10⁻³⁴ Js
ν is frequency of radiation.=10¹⁴Hz
Energy E=6.62 x10⁻³⁴x10¹⁴
=6.62 x 10⁻²⁰ J

Number of photons = Overall Given energy/ Energy of single photon.
=6.6 2J/6.62 x 10⁻²⁰
=10²⁰
∴The number of photons of frequency 10¹⁴ Hz in radiation of 6.62j will be 10²⁰.