There are two plane mirrors with reflecting surfaces facing each other. The mirrors are moving with speed $v$ away from each other. $A$ point object is placed between the mirrors. The velocity of the $n$-th image will be

The image of an object approaching a convex mirror of radius of curvature $20 \ m$ along its optical axis is observed to move from $25/3 \ m$ to $50/7 \ m$ in $30 \ s$. The speed of the object in $km/hr$ is

The origin of $x$ and $y$ coordinates is the pole of a concave mirror of focal length $20\, cm$. The $x$-axis is the optical axis with $x > 0$ being the real side of the mirror. $A$ point object at the point $(25\, cm, 1\, cm)$ is moving with a velocity $10\, cm/s$ in the positive $x$-direction. The velocity of the image in $cm/s$ is approximately:

$A$ point object is moving uniformly towards the pole of a concave mirror of focal length $25 \ cm$ along its axis as shown below. The speed of the object is $1 \ ms^{-1}$. At $t=0$,the distance of the object from the mirror is $50 \ cm$. The average velocity of the image formed by the mirror between time $t=0$ and $t=0.25 \ s$ is

$A$ point object on the principal axis at a distance $1.5\, cm$ in front of a concave mirror of radius of curvature $20\, cm$ has velocity $2\, mm/s$ perpendicular to the principal axis. The velocity of image at that instant will be.....$mm/s$

$A$ convex mirror of focal length $20 \, cm$ is fitted in a car. $A$ second car,which is $2.8 \, m$ away,overtakes the first car at a relative speed of $15 \, m/s$. What will be the speed of the second car as observed in the mirror of the first car?