An object $5 \ cm$ tall is placed $1 \ m$ from a concave spherical mirror which has a radius of curvature of $20 \ cm$. The size of the image is $...... \ cm$.

If $x$ is the distance of an object from the focus of a concave mirror and $y$ is the distance of the image from the focus, then which of the following graphs is correct between $x$ and $y$?

An object is placed at $20 \ cm$ in front of a concave mirror,which produces a three times magnified real image. What is the focal length of the concave mirror (in $cm$)?

An object is placed $40\;cm$ from a concave mirror of focal length $20\;cm.$ The image formed is

$A$ driver sitting inside a parked car is watching vehicles approaching from behind with the help of a side-view mirror,which is a convex mirror with a radius of curvature $R = 2 \ m$. Another car approaches from behind with a uniform speed of $90 \ km/h$. When the car is at a distance of $24 \ m$ from the mirror,the magnitude of the acceleration of the image in the side-view mirror is $a$. The value of $100a$ is $m/s^2$.

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