Why does the resistance of an LDR decrease when the light intensity increases?
An LDR is usually made of a semiconductor material(Normally Silicon) doped with a small percentage of a valency 5 material (commonly Arsenic), to make it an “N” material. The photons of the light affecting the LDR, charge the electrons of the doped material so that they can easily be dislodged by any electrical charges thus allowing the current to flow more easily. The increase of current flow for the same PD proves that the resistance of the device has been reduced by the increase of light.
