Advertisements
Advertisements
प्रश्न
Draw a diagram to show how a converging lens focusses parallel rays of light?
उत्तर
When rays of light from a distant object pass through a converging lens, the light rays converge at the focus of lens (fig.).
APPEARS IN
संबंधित प्रश्न
Define the principal focus of a concave lens.
List some things that concave lens and concave mirror have in common.
Which type of lens is
a diverging lens? Explain your answer with diagrams.
When sunlight is concentrated on a piece of paper by a spherical mirror or lens, then a hole can be burnt in it. For doing this, the paper must be placed at he focus of:
(a) either a convex mirror or convex lens
(b) either a concave mirror or concave lens
(c) either a concave mirror or convex lens
(d) either a convex mirror or concave lens
Give two characteristic of the image formed by a concave lens.
An object of height 4 cm is kept at a distance of 30 cm from a concave lens. Use lens formula to determine the image distance, nature and size of the image formed if focal length of the lens is 15 cm.
An object is placed at a distance 24 cm in front of a convex lens of focal length 8 cm.
(i) What is the nature of the image so formed?
(ii) Calculate the distance of the image from the lens.
(iii) Calculate the magnification of the image.
A concave lens has a focal length 30 cm. Find the position and magnification (m) of the image for an object placed in front of it at distance 30 cm. State whether the image is real or virtual?
State three characteristics of the image of an extended source, formed by a concave lens.
Do we expect any change in the position, nature, and size of the image
(i) formed by a concave lens,
(ii) with a change in the position of the object?
