MHT CET202123 Sep 2021Evening ShiftPhysicsDual Nature of MatterActual
When wavelength of incident radiation on the metal surface is reduced from ' ₁ ' to ' ₂ ' the kinetic energy of emitted photoelectrons is tripled. The work function of metal [ h = Plank 's constant, c = velocity of light]
Options
- Ahc 2 [ 3 ₁- ₂ ₁ ₂ ]
- Bhc 2 [ 3 ₂- ₁ ₁ ₂ ]
- Chc [ 3 ₁- ₂ ₁ ₂ ]
- Dhc [ 3 ₂- ₁ ₁ ₂ ]
Correct answer
B. hc 2 [ 3 ₂- ₁ ₁ ₂ ]
Step-by-step solution
Let K represent kinetic energy aligned & K ₁= hc ₁ - W ₀ & and K ₂= hc ₂ - W ₀ & ~K ₂=3 ~K ₁ & hc ₂ - W ₀=3 hc ₁ -3 ~W ₀ & 2 ~W ₀= 3 hc ₁ - hc ₂ & W ₀= hc 2 ( 3 ₂- ₁ ₁ ₂ ) aligned