Explain why, we cannot see our surroundings clearly when we enter a darkened cinema hall from bright sunshine but our vision improves after some time.
It is because in bright sunlight the size of the pupil of our eye is small. So, as we enter the darkened cinema hall very little light enter our eye and we cannot see things properly. Later, the pupil of our eye expands and becomes large and more light enters our eye because of which we can see clearly.