Wavelength 400 nm light
- Light of wavelength 400 nm is incident on a metal surface
- Light of wavelength 400 nm is incident
- Light of wavelength 400 nm strikes a certain metal
- Light of wavelength 400 nm is incident continuously on a cesium ball
- Light of wavelength 400 nm is shone on a metal surface in an apparatus
- Light of wavelength 400 nm falls on a metal surface
- When light of wavelength 400 nm is incident on the cathode of a photocell
- Monochromatic light of wavelength 400 nm
- A light of wavelength 400 nm is incident on a photosensitive
- A light of wavelength 400 nm is incident on a photosensitive material