(a) With the help of a labelled diagram explain how a convex lens converges a beam of parallel light rays. Mark the principal axis, optical centre, principal focus and focal length of the convex lens on the diagram. (b) State whether the convex lens has a real focus or a virtual focus. (c) List some things that convex lens and concave mirror have in common.
(a) With the help of a labelled diagram, explain how a concave lens diverges a beam of parallel light rays. Mark the principal axis, optical centre, principal focus and focal length of the concave lens on the diagram. (b) State whether concave lens has a real focus or a virtual focus. (c) List some things that concave lens and convex mirror have in common.