Fill in the blanks in the following.

(a) A person 1 m in front of a plane mirror seems to be …………… m away from his image.

(b) If you touch your …………… 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 ……………

(c) The size of the pupil becomes …………… when you see in dim light.

(d) Night birds have …………… cones than rods in their eyes.

(a) A person 1 m in front of a plane mirror seems to be 2 m away from his image.

Reason — When a person stands in front of a plane mirror, their image appears to be as far behind the mirror as the person is in front of it.
So, when the person is 1 m away from the mirror. His image will be formed at 1 m from the mirror on the other side, hence, his image will be 1 + 1 = 2 m from the person himself.

(b) 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.

Reason — The image formed by a mirror is laterally inverted hence, when we touch our left ear with our right hand in front of a plane mirror, it will be seen in the mirror that our right ear is touched with our left hand.

(c) The size of the pupil becomes large when you see in dim light.

Reason — In dim light conditions, there's less available light for vision. To allow more light to enter the eye and improve visibility in low-light environments, the iris dilates the pupil. When the pupil dilates, it enlarges in size, allowing more light to pass through the eye and reach the retina at the back of the eye.

(d) Night birds have fewer cones than rods in their eyes.

Reason — Having fewer cones and more rods allows night birds to have better night vision. Rods are more sensitive to low levels of light, making them ideal for detecting prey and navigating in the dark. Additionally, having fewer cones means that night birds likely have reduced color vision or even monochromatic vision, which is less important for hunting in low-light conditions.