Car $B$ overtakes another car $A$ at a relative speed of $40 \, ms^{-1}$. How fast will the image of car $B$ appear to move in the mirror of focal length $10 \, cm$ fitted in car $A$,when the car $B$ is $1.9 \, m$ away from the car $A$? (In $ms^{-1}$)

When an object is kept at a distance of $30\, cm$ from a concave mirror,the image is formed at a distance of $10\, cm$ from the mirror. If the object is moved with a speed of $9\, cm/s$,the speed (in $cm/s$) with which the image moves at that instant is:

The speed at which the image of a luminous point object is moving,if the luminous point object is moving at speed $v_0$ towards a spherical mirror along its axis,is (Given: $r =$ radius of curvature,$u =$ object distance):

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

If an object moves towards a plane mirror with a speed $v$ at an angle $\theta$ to the normal of the plane of the mirror,find the relative velocity between the object and the image.

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: