The focal length of a convex mirror is $20\, cm$. Its radius of curvature will be.....$cm$.

An object is placed at $10 \text{ cm}$ in front of a concave mirror of focal length $15 \text{ cm}$. The image formed will be . . . . . . .

For a real object,which of the following can produce a real image?

Distance between an object and its three times magnified real image is $40 \ cm$. The focal length of the mirror used is . . . . . . $cm$.

An object is placed at a distance of $10 \, cm$ from a concave mirror of focal length $20 \, cm$. The image formed will be .......

An object is at a distance $x_1$ from the focus of a concave mirror,and its image is formed at a distance $x_2$ from the focus. The focal length of the mirror is: