What do you mean by image distance?

The radius of curvature of a converging mirror is $30 \mathrm{cm}$. At what distance from the mirror should an object be placed so as to obtain a virtual image?

Which of the following statements is not true in reference to the diagram shown above?

An object is placed at a distance $24 \mathrm{cm}$ in front of a convex lens of focal length $8 \mathrm{cm}$.
(i) Calculate the distance of the image from the lens.
(ii) Calculate the magnification of the image.

A student holding a mirror in his hand, directed the reflecting surface of the mirror towards the Sun. He then directed the reflected light on to a sheet of paper held close to the mirror.

Which type of mirror does he have?

An object of height $4 \mathrm{cm}$ is kept at a distance of $30 \mathrm{cm}$ from the pole of a diverging mirror. If the focal length of the mirror is $10 \mathrm{cm}$, the height of the image formed is ____.

Draw a ray diagram to show the formation of an image when an object is placed between $\mathrm{F}$ and $\mathrm{P}$ of a concave mirror.

In which of the following is a concave mirror is used?

A virtual, diminished image is formed when an object is placed between the optical centre and the principal focus of a lens.
(i) Name the type of lens which forms the above image.
(ii) Draw a ray diagram to show the formation of the image with the above stated characteristics.  

What should he do to burn the paper?

Observe the following figure and complete the table.

Observe the following diagram and answer the question given below

Explain why a ray of light passing through the centre of curvature of a concave mirror gets reflected back along the same path.

An object is placed at a distance of $15 \mathrm{cm}$ in front of a Concave Mirror. If an image of its is formed at $30 \mathrm{cm}$ from the mirror, find the focal length of the mirror.

A concave mirror produces $3$ times enlarged image of an object placed $10 \mathrm{cm}$ in front of it. Calculate its radius of curvature.

For the diagram shown, according to the new Cartesian sign convention the magnification of the image formed will have the following specifications.

A student holding a mirror in his hand, directed the reflecting surface of the mirror towards the Sun. He then directed the reflected light on to a sheet of paper held close to the mirror.

Will he be able to determine the approximate value of focal length of this mirror from this activity ? Give reason and draw ray diagram to justify your answer in this case.