Advertisements
Advertisements
Question
A converging lens is used to produce an image of an object on a screen,object on a screen. What change is needed for the image to be formed nearer to the lens?
(a) increase the focal length of the lens
(b) insert a diverging lens between the lens and the screen
(c) increase the distance of the object from the lens
(d) move the object closer to the lens
Solution
Increase the distance of the object from the lens
As the object moves away from the lens, the image gets closer to the lens.
APPEARS IN
RELATED QUESTIONS
Give the position, size and nature of image of formed by a concave lens when the object is placed:
at infinity.
Which type of lens is :
a converging lens, and which is
With the help of a diagram, explain why the image of an object viewed through a concave lens appears smaller and closer than the object.
A beam of light is incident through the holes on one side of a box and emerges out through the holes on its opposite side as shown in the following figure:
The box contains:
(a) a glass prism
(b) a concave lens
(c) a convex lens
(d) a parallel-sided glass slab
When an object is placed 10 cm in front of lens A, the image is real, inverted, magnified and formed at a great distance. When the same object is placed 10 cm in front of lens B, the image formed is real, inverted and same size as the object.
What is the nature of lens B?
Where will the image be formed if an object is kept in front of a concave lens at a distance equal to its focal length? Draw a ray diagram to illustrate your answer.
- Name the lens which always forms an erect and virtual image.
- State whether the image in part (a) is magnified or diminished.
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.
Convex lens : converging : : concave lens : _______
Identify the device used as a spherical mirror or lens in following case, when the image formed is virtual and erect in case.
Object is placed between infinity and device, image formed is diminished and between focus and optical centre on the same side as that of the object.
