A convex lens can produce the complete image of the object even though half of the lens is covered. This is because light coming from the object can be refracted from the other half of the lens. However, the intensity of light will be reduced.

Cover half the lens If we cover the top half of the lens, the image just gets dimmer. This tells us that light from all parts of the object goes through all of the lens and then forms the image, so we’re losing about half the light from every part of the object when we block half the lens.

Every part of a lens forms a complete image. If the lower part of the lens is blackened, even then complete image will be formed but its intensity will decrease.

Note: Even if half of the convex lens is covered with a black sheet of paper, the lens will produce a complete image of the object. However, the intensity of the image will be less and the image formed will be less bright as compared to the one formed by a complete convex lens.

As the image formed by a large number of rays from the object.so,if any part of the lens is covered,the image will form. the brightness of image will be less compared to the image formed by without wrapping the lens.

Explanation: If the plane mirror is covered with a black paper then the complete image of the object will be formed. But the intensity of the image of the object will be reduced. As the reflected rays will be less.

Summary. A plane mirror always forms a virtual image (behind the mirror). The image and object are the same distance from a flat mirror, the image size is the same as the object size, and the image is upright.

(i) Image formed will be inverted diminished between C and F. ii) When the lower half of the mirror’s reflecting surface is painted black, the position of the image and its intensity will get reduced. A small candle, 2.5 cm in size is placed at 27 cm in front of a concave mirror of radius of curvature 36 cm.

Concave mirrors form both real and virtual images. When the concave mirror is placed very close to the object, a virtual and magnified image is obtained and if we increase the distance between the object and the mirror, the size of the image reduces and real images are formed.

Concave Mirror

To summarize

The type of mirror utilized in both situations is a concave mirror. Additional Information: Solar/rear view of vehicle: it is a convex mirror because it gives diminished, virtual and an erect image of the side or rear with a wider field of view.