Physics
An object is placed at a distance of 20 cm in front of a concave lens of focal length 20 cm. Find —
(a) the position of the image, and
(b) the magnification of the image
Related Questions
Draw a neat labelled ray diagram to show the formation of an image by a magnifying glass. State three characteristics of the image.
Describe in brief how would you determine the approximate focal length of a convex lens.
The diagram in figure shows the experimental setup for determination of the focal length of a lens using a plane mirror.
(i) Draw two rays from the point O of the object to show the formation of image I at O itself.
(ii) What is the size of the image I?
(iii) State two more characteristics of the image I.
(iv) Name the distance of the object O from the optical centre of the lens.
(v) To what point will the rays return if the mirror is moved away from the lens by a distance equal to the focal length of the lens?
Describe how you would determine the focal length of a converging lens, using a plane mirror and one pin. Draw a ray diagram to illustrate your answer.