An object is placed at a distance of $20 \text{ cm}$ in front of a concave mirror of focal length $10 \text{ cm}$. Where will the image be formed?

Define lateral magnification.

Show that the mirror formula for spherical mirrors also holds for a plane mirror.

$A$ $4.5 \, cm$ needle is placed $12 \, cm$ away from a convex mirror of focal length $15 \, cm$. Give the location of the image and the magnification. Describe what happens to the image as the needle is moved farther from the mirror.

Define linear magnification produced by a spherical mirror. Also,give its relation.

$A$ student wants to project the image of a candle flame on a screen $60\, cm$ in front of a mirror by keeping the flame at a distance of $15\, cm$ from its pole.
$(a)$ Write the type of mirror he should use.
$(b)$ Find the linear magnification of the image produced.
$(c)$ What is the distance between the object and its image?
$(d)$ Draw a ray diagram to show the image formation in this case.