Experiment Description

Experiment

Experiment C11    The Focal Length of a Concave Lens

Objectives
  • Study the virtual image formed by a concave lens
  • Determine the focal length of a concave lens using a plane mirror and a convex lens
  • Determine the focal length of a concave lens using a convex lens
Description
In this activity, you will measure the focal length of a concave lens using several methods.

In Experiment 1, you will measure the focal length of the concave lens using the reversibility of light.

In Experiment 2, you will use graphical method to determine the focal length of the concave lens with the help of a convex lens.
Apparatus
concave lens on a holder (focal length not greater than 15 cm) [1]
thick convex lens on a holder (focal length 10 cm) [1]
plane mirror [1]
metre rule / optical bench [1]
illuminated object [1]
translucent screen [1]
optical pin on a cork [1]
concave mirror on a holder (focal length 15 cm) [1]
Experiment