Verified Solution • 2025–26 Session moderate

QJEEM19Ph1187: JEE Main 2019 Physics - Class 12 JEEM19Ph1187 Solution: When a certain photosensitive surface is illuminated with…

When a certain photosensitive surface is illuminated with monochromatic light of frequency v, the stopping potential for the current is –V0/2. When the surface is illuminated by monochromatic light of frequency v/2, the stopping potential is – V0. The threshold frequency for photoelectric emission is :

Multiple Choice Options

  • A 2v
  • B 43v
  • C 3v2
  • D 5v3

Step-by-Step Verified Solution

Einstein’s photoelectric equation in the two cases is given by

eV0ΔE=hυ−hυ0 ......(i)

and eV0=hυ2−hυ0 .....(ii)

From eqn. (i) and (ii),

12=hυ−hυ0hυ2−hυ0

⇒ υ0=32υ

Related Learning Resources & Exam Preparation

JEE Main PYQ Question Bank
Browse year-wise authentic previous years' questions with solutions
Authentic CBT Mock Tests
Simulate official exam environment with live timer and percentile scoring