MHT CET Medical202622 April 2026Evening ShiftPhysicsDual Nature of MatterActual
The de-Broglie wavelength of the free electron is ' ' and has a kinetic energy E_k . If the kinetic energy of the free electron is made double, the new de-Broglie wavelength is ' ₁ '. If ₁ = x , , then the value of x is
Options
- A1 2
- B1 2
- C2
- D2
Correct answer
B. 1 2
Step-by-step solution
The de-Broglie wavelength of an electron with kinetic energy E_k is given by = h 2mE_k When the kinetic energy is doubled, the new kinetic energy is E_k' = 2E_k . The new de-Broglie wavelength ₁ becomes ₁ = h 2m(2E_k) = 1 2 h 2mE_k ₁ = 1 2 Given ₁ = x , comparing the two expressions gives x = 1 2 Answer: 1 2