the energy of photon having wavelength 700nm is
Answers
Answer:
As h and c are both constants, photon energy E changes in inverse relation to wavelength λ. Therefore, the photon energy at 1 μm wavelength, the wavelength of near infrared radiation, is approximately 1.2398 eV.
Given:
A photon has a wavelength of 700 nanometres.
To Find:
The energy of the photon is?
Solution:
The given problem can be solved using the concepts of atomic structure.
1. The energy of a photon with Planck's const h and wavelength λ is given by the formula,
=>E = (h*c)/ λ (where c is the speed of the light )
2. Substitute the given data, The value of (h) is 6.626 x 10^-34 J-s, the value of c is 3 x 10^8 m/s.
=> E = (h*c)/ λ = 1242 (electron volts)/λ(nanometers),
=> E = 1242/700 = 621/350 = 1.774eV.
3. In other units,
=> E = (h*c)/ λ,
=> E = (6.62*10^-34*3*10^8)/700*10^-9,
=> E = (6.62*3*10^-26)/7x10^-7,
=> E = (19.86 * 10^-19)/7,
=> E = 2.837 * 10^ -19 Joules.
Therefore, the energy of the photon is 1.774 eV (OR) 2.837 * 10^-19 Joules.