Physics · PYQ NEET UG 2016(1)

When a metallic surface is illuminated with radiation of wavelength \( \lambda \), the stopping potential is \( V \). If the same surface is illuminated with radiation of wavelength \( 2\lambda \), the stopping potential is \( \frac{V}{4} \). The threshold wavelength for the metallic surface is

1. A
   \( 5\lambda \)
2. B
   \( 3\lambda \)
3. C
   \( 4\lambda \)
4. D
   \( 5\lambda/2 \)