Question

We usually do not see bright colours in dim light.why?

Answer 1

Our eyes consist of two types of photoreceptors — rods and cones. Rods are functional when light is dim, thus it is used  for night vision. On the other hand, cones require more light to be activated and are responsible for colored vision. Since coloured lights are difficult to detect when dimly lit, rods do not aid in color vision. This is why we cannot recognize bright hues in dim light.