Draw ray diagram in each case to show the position and nature of the image formed when the object is placed at the centre of curvature of a concave mirror.

Draw ray diagram in each case to show the position and nature of the image formed when the object is placed between the pole P and focus F of a concave mirror.

Draw ray diagram in each case to show the position and nature of the image formed when the object is placed in front of a convex mirror.

Draw ray diagram in each case to show the position and nature of the image formed when the object is placed at $2\mathrm{F}$ of a convex lens.

Draw ray diagram in each case to show the position and nature of the image formed when the object is placed in front of a concave lens.

An object $3 \mathrm{cm}$ high produces a real image $4.5 \mathrm{cm}$ high, when placed at a distance of $20 \mathrm{cm}$ from a concave mirror. Calculate the position of the image.

An object $3 \mathrm{cm}$ high produces a real image $4.5 \mathrm{cm}$ high, when placed at a distance of $20 \mathrm{cm}$ from a concave mirror. Calculate the focal length of the mirror.