Question

When we enter the cinema hall, we cannot see properly for a short time. This is because
A. Pupil does not open
B. Pupil does not close
C. Adjustment of pupil takes time
D. None

Answer 1

Hint: In this question we are asked the reason as to why we cannot see properly when we enter cinema hall. Therefore, we will be discussing the reason behind this phenomenon and elaborate it further. We know that our pupils are capable of dilating when introduced to various intensities of light. We will be using this concept to define our reason for the given statement.

Complete step-by-step answer:
When we enter the cinema hall, we are unable to see everything clearly. Now, we know that the cinema hall is kept in dark for the better experience of the movie. No outside light is allowed to interfere with the rays coming from the projector in the cinema hall. Even though it is dark in the cinema hall a very small intensity light is always present in cinema hall. We are anyways still unable to see clearly in such light. Now, we know that our eyes adjust according to the intensity of light. When we are exposed to bright sunlight or light from an electric bulb our pupils contract. As the light is bright, the pupils have no need to dilate as the light will directly enter our eyes after reflecting on the surface. However, in a low light atmosphere the pupils tend to dilate or get bigger. As there is low light, the pupils dilate in order to let more amount of light reach our retina.
Before entering the cinema hall we are exposed to bright light. So, as soon as we enter the low light atmosphere of the cinema hall our pupils take time to dilate. Which means that the pupils take time to adjust to the surrounding. Therefore, for a short period of time after we enter the cinema hall we cannot see properly, as the pupils take time to adjust.

So, the correct answer is “Option C”.

Note: The black centre in the eye is called the pupil. The function of the pupil is to let the light in the eye and focus it on the retina in order for us to see. The iris is controlled by the muscles in the iris. The iris is the coloured part in the eye around the pupil. If the iris is injured it may no longer be able to control the dilation and contraction of pupil, leading to eye disorders.