MHT CET20225 Aug 2022Morning ShiftPhysicsDual Nature of MatterActual
A photoelectric surface is illuminated successively by monochromatic light of wavelength ' ( ) ' and ' ( 2 ) . If the maximum kinetic energy of the emitted photoelectrons in the first case is one-third that in the second case, the work function of the surface of the material is ( c = speed of light, h = Planck's constant.)
Options
- A2 hc
- Bhc 2
- Chc
- Dhc 3
Correct answer
B. hc 2
Step-by-step solution
The correct option is (B). Concept: Einstien's Photoelectric effect theory The maximum kinetic energy K of the photoelectric electrons is related to the incident wavelength and work function of the metal as follows: K = hc - For the incident wavelength , the equation is K = hc - And for the incident wavelength 2 , the equation is 3 K= hc 2 - Taking the ratio of two equations: 1 3 = ( hc - ) ( hc 2 - ) On solving, we get = hc 2