Science questions in on sentence. [1 M]

Always.

Night birds have less cones than rods in their eyes.Expalantion:
(Night birds can see in the night, but not in the day. They have on their retina a large number of rod cells and only a few cones).

The size of the pupil becomes large when you see in dim light.Expalantion:
(In dim light, the amount of light entering the eye is very little. To increase the amount of light, the pupil expands).

In people (particularly old aged) suffering from cataract, the eye lens becomes clouded. Cataract is treated by replacing the opaque lens with a new artificial lens.

Braille (Braille is named after its creator- Louis Braille).

If you touch your left ear with your right hand in front of a plane mirror, it will be seen in the mirror that your right ear is touched with your left hand.

Expalantion:

(This is because of lateral inversion of images formed in a plane mirror).

Convex lens is present in our eyes, which focuses light on the back of the eye, on a layer called retina. So, it forms the image of an object at retina.

The splitting of white light into seven colours is known as dispersion of light.

When an image formed by a plane mirror is such that the left of the object appears on the right and the right appears on the left. This is known as lateral inversion.

It is system of raised dots that can be read with the fingers by blind people or people who have low vision.

Best way to learn and write Braille system is - The Hadley Institute for the Blind and Visually Impaired.

Blind spot.

Human eye have crystalline lens called convex lens.

Iris control the size of the pupil.

The ray is reflected infinite number of times between the two plane mirrors placed parallel to each other.

If there are no photoreceptors, the brain will get no information about the image formed at retina and thus nothing could be seen.

The phenomenon which is responsible for seeing movies in a cinema hall is Persistence of vision.

virtual, behind the mirror and of the same size as the object.