Photoelectrons are emitted from a metal when illuminated by light of fixed frequency above threshold. The optical power begins to decrease linearly with time. Which pair of plots best describes photocurrent I and stopping-potential magnitude |Vₛ| versus time? Image (four graph pairs)

Options

• Option A

  Photocurrent decreases linearly; stopping potential remains constant (Image-1)

• Option B

  Both photocurrent and stopping potential decrease (Image-2)

• Option C

  Photocurrent remains constant; stopping potential decreases (Image-3)

• Option D

  Both photocurrent and stopping potential remain constant (Image-4)