In a photoelectric experiment, the wavelength of incident light is increased from $5×10^{-10} m$ to $9×10^{-10} m$, while the intensity of radiation remains the same. Choose the correct statement from the following.
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → The cut off potential will decrease
Stopping potential = $K.E_{max}=E-\phi$
$=\frac{hc}{λ}-\phi$
∵, stopping potential $∝ \frac{1}{λ}$
∴, cut off potential will decrease.