An object approaches a convex mirror of radius of curvature $20 \,m$ along its optical axis. The image is observed to move from $\frac{25}{3} \,m$ to $\frac{50}{7} \,m$ from the mirror in $30 \,s$. What is the speed of the object in $km/h$?

$A$ point object is moving on the principal axis of a concave mirror of focal length $24 \; cm$ towards the mirror. When it is at a distance of $60 \; cm$ from the mirror,its velocity is $9 \; cm/s$. What is the velocity of the image at that instant?

$A$ point object is moving on the principal axis of a concave mirror of focal length $24\;cm$,towards the mirror. When it is at a distance of $60\;cm$ from the mirror,its velocity is $9\;cm/sec$. What is the velocity of the image at that instant?

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 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:

An object is moving with a velocity of $2 \ m/s$ to the left,and a plane mirror is moving with a velocity of $9 \ m/s$ to the right. Find the velocity of the image with respect to the ground.