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 bob of a pendulum is released from position $P$. What is the velocity of the image of the bob on the mirror $M$ at position $Q$ with respect to the bob?

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.

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):

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:

$A$ 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?