Experiment Description

Experiment

Experiment C10    The Focal Length of a Convex Lens

Objectives
  • Learn the technique of locating real image by no-parallax method
  • Study the real image formed by a convex lens
  • Determine the focal length of a convex lens by graphical method
  • Determine the focal length of a convex lens by conjugate foci method
Description
In this activity, you will measure the focal length of a convex lens using several methods.

In Experiment 1, you will use the convex lens to produce a real image of a distant object and capture the image on a screen.

In Experiment 2, you will locate the focus of the convex lens using no-parallax method with the help of a plane mirror.

In Experiment 3, you will use graphical method to determine the focal length of the convex lens.

In Experiment 4, you will measure the focal length of the convex lens by lens displacement method using conjugate foci.
Apparatus
convex lens on a holder (focal length not greater than 15 cm) [1]
metre rule / optical bench [1]
illuminated object [1]
translucent screen [1]
plane mirror [1]
optical pin on a cork [1]
convex lens of the same focal length as above [1]
Experiment