Suppose that the lower half of the concave mirror's reflecting surface in the figure is covered with an opaque (non-reflective) material. What effect will this have on the image of an object placed in front of the mirror?

$A$ straight line joining the object point and image point is always perpendicular to the mirror:

The convergence of a concave mirror can be decreased by dipping it in which of the following?

An object is placed at a distance $u$ from a concave mirror of focal length $f$. $A$ real image is formed on a screen placed at a distance $v$ from the mirror. As $u$ changes,$v$ also changes. Which of the following graphs correctly represents the variation of $1/v$ with $1/u$?

Derive the relationship between the focal length $(f)$ and the radius of curvature $(R)$ for a spherical mirror.

Suppose while sitting in a parked car,you notice a jogger approaching towards you in the side view mirror of radius of curvature $R = 2 \; m$. If the jogger is running at a speed of $5 \; m s^{-1}$,how fast does the image of the jogger appear to move when the jogger is $(a) \; 39 \; m$,$(b) \; 29 \; m$,$(c) \; 19 \; m$,and $(d) \; 9 \; m$ away?