Answer the following questions :
State uses of a convex lens .

Answer the following questions : State uses of a concave lens .

Answer the following questions : State two uses of a convex lens.

Answer the following questions : State two uses of a concave lens.

Answer the following questions : In the case of a convex lens , show the path of the refracted ray when the incident ray of light is parallel to the principal axis of the lens passes through the focus of the lens passes through the optical centre of the lens.

Answer the following questions: State uses of a concave mirror.

Answer the following questions : State the use of a telescope .

Answer the following questions : State the uses of ethanol.

Answer the following questions : State two uses of a compound microscope .

Answer the following questions: State the use of a periscope.