Question

How to calculate the effective mass of the photon of wavelength 1 A°?

Answer 1

1. lamda = 3.6 angstrom = 3.6 x 10^-10 m.

2. velocity of photon = velocity of light.

3. m = h/lamda*v ( from de-brogile's equation)

4. m = 6.626 x 10^-34/3.6 x10^-10 x 3 x 10^8.

5. m = 6.626 x 10^-32/10.8.

6. m = 0.6135 x 10^-32.

7. m = 6.135 x 10^-33 kg.

Answer 2

Answer:

The effective mass of the photon of wavelength $1\AA$ calculated is $2.2\times 10^{-32}kg$.

Explanation:

Given data,

The wavelength of the photon, λ = $1\AA$ = $10^{-10}m$

The photon's effective mass, m =?

From the de-Broglie hypothesis given below, we can find out the effective mass of the photon:

• λ = $\frac{h}{mc}$

Here,

• h = Planck's constant = $6.6\times 10^{-34} J-s$
• c = Light's speed = $3\times 10^{8} m/s$

Thus,

• m = $\frac{h}{\lambda c}$
• m = $\frac{6.6\times 10^{-34}}{10^{-10}\times 3\times 10^{8} }$
• m = $2.2\times 10^{-32}kg$

Hence, the photon's effective mass, m = $2.2\times 10^{-32}kg$.