Question

Which of the following electromagnetic waves has photons of largest momentum?

• A. X-rays
• B. AM radio waves
• C. Microwaves
• D. TV waves

Hint:

The momentum of a photon is directly proportional to its frequency. Since X-rays have the highest frequency, their photons carry the largest momentum.

Answer 1

The Correct Option is A

The momentum of a photon is determined by its wavelength. The relationship between the momentum (p) of a photon and its wavelength (λ) is given by the equation:

p = \(\frac{h}{λ}\)

where h is Planck's constant. From this equation, it is evident that momentum is inversely proportional to wavelength. This implies that, the shorter the wavelength, the greater the momentum of the photon.

Electromagnetic waves, in order of increasing wavelength, are:

• X-rays
• TV waves
• Microwaves
• AM radio waves

Since X-rays have the shortest wavelength among the given options, they also have the largest momentum according to the relationship between photon momentum and wavelength.

Thus, the electromagnetic waves with photons of the largest momentum are X-rays.