MCQ
Light of wavelength $\lambda$ strikes a photo-sensitive surface and electrons are ejected with kinetic energy E. If the kinetic energy is to be increased to 2E, the wavelength must be changed to $\lambda^{\prime}$ where
- A$\lambda^{\prime}=\frac{\lambda}{2}$
- B$\lambda^{\prime}=2 \lambda$
- ✓$\frac{\lambda}{2}<\lambda^{\prime}<\lambda$
- D$\lambda^{\prime}>\lambda$
