JEE Main202127 Aug 2021Evening ShiftPhysicsDual Nature of MatterActual
A monochromatic neon lamp with wavelength of 670 . 5 nm illuminates a photo-sensitive material which has a stopping voltage of 0 . 48 V . What will be the stopping voltage if the source light is changed with another source of wavelength of 474 . 6 nm ?
Options
- A0 . 24   V
- B1 . 5   V
- C1 . 25   V
- D0 . 96   V
Correct answer
C. 1 . 25   V
Step-by-step solution
eV s = hc λ - ϕ e V ' - V = h c 1 λ ' - 1 λ V ' = hc e 1 λ ' - 1 λ + V = 1240 1 474 - 1 670 + 0 . 48 = 1 . 25 eV