Light Mirrors and Lenses Class 8 Short Question Answer

Light Mirrors and Lenses Class 8 Short Question Answer

Light Mirrors and Lenses Class 8 Short Question Answer

Question 1.

What happens to the appearance of a pencil placed behind a glass tumbler filled with water?

Answer:

The pencil appears bent or displaced due to the refraction of light as it passes from air into water, changing its direction.

Question 2.

Why are convex mirrors preferred for observing traffic behind vehicles?

Answer:

Convex mirrors provide a wider field of view, allowing drivers to see more of the area behind them compared to plane mirrors.

Question 3.

What is the difference between a concave mirror and a convex mirror?

Answer:

A concave mirror has a reflecting surface that curves inward, while a convex mirror has a reflecting surface that curves outward.

Question 4.

What is the angle of incidence in relation to the angle of reflection according to the laws of reflection?

Answer:

The angle of incidence is always equal to the angle of reflection when a ray of light strikes a reflective surface.

Question 5.

How do solar cookers utilise mirrors to generate heat?

Answer:

Solar cookers use mirrors to converge sunlight onto a focal point, which generates heat for cooking food.

Question 6.

What is the difference between a concave mirror and a convex mirror in terms of image formation?

Answer:

A concave mirror can produce both real and virtual images depending on the object's distance from the mirror, while a convex mirror always produces virtual images that are smaller and upright.

Question 7.

How does a lens change the appearance of objects viewed through it?

Answer:

A lens can magnify or reduce the size of objects depending on its shape. For example, a convex lens makes objects appear larger, while a concave lens makes them appear smaller.

Question 8.

What is the significance of the curved surface of a water drop in relation to lenses?

Answer:

The curved surface of a water drop acts like a lens by bending light rays that pass through it, which can enlarge the appearance of objects viewed beneath it. This principle is similar to how magnifying glasses work.