NEETPhysicsDual Nature of Matter
Two photons propagating in a vacuum have their momenta in the ratio 1 : 4 . What will be the ratio of their respective energies and the ratio of their speeds?
Options
- A1 : 16 and 1 : 4
- B1 : 4 and 1 : 1
- C4 : 1 and 1 : 1
- D1 : 4 and 1 : 4
Correct answer
B. 1 : 4 and 1 : 1
Step-by-step solution
For a photon, the energy E and momentum p are related by the equation E = pc , where c is the speed of light in vacuum. Since the speed of all photons in a vacuum is a universal constant ( c ), the ratio of their speeds is v₁ : v₂ = 1 : 1 . Because c is constant, the energy E is directly proportional to the momentum p . Therefore, the ratio of their energies is equal to the ratio of their momenta: E₁ E₂ = p₁ p₂ = 1 4 Thus, the ratio of their energies is 1 : 4 and the ratio of their speeds is 1 : 1 . Answer: 1 : 4 a