Question

Two photons of
(a) equal wavelength have equal linear momenta
(b) equal energies have equal linear momenta
(c) equal frequencies have equal linear momenta
(d) equal linear momenta have equal wavelengths

Answer 1

Two photons of - (d) equal linear momenta have equal wavelengths.

Linear moments of photons can is given by the formula - p= h/lambda.

The equation is commonly knows as de Broglie's equation.

In the equation, p represents momentum, h represents Plank's constant and lambda represents wavelength.

Energy of a photon is given by the equation - E = hf or E = hc/lambda

Hence E is representative of energy, h again represents Plank's constant f is for frequency, c is for speed of light and lambda is for wavelength.

Since, formula for fourth option equates, hence it is the answer..

Answer 2

Two photons of which is equal wavelengths can be seen with equal linear momenta.

Explanation:

• In the rest of the options, the magnitude of energy or momentum can be identical.
• This is due to the reason that the momentum and energy are inversely proportional to wavelength.
• So, two photons have equal wavelengths have equal linear momenta. It should also be noted that the photons’ propagation direction should be different. This is the reason why option D is correct.