Which mirror is used by dentists?

What are the advantages and disadvantages of using a convex mirror for seeing traffic at the rear?

For which type of mirror will the image always be erect,regardless of the distance at which the object is placed?

Why does a light ray incident on a rectangular glass slab immersed in any medium emerge parallel to itself? Explain.

What is meant by power of a lens? Define its $SI$ unit. You have two lenses $A$ and $B$ of focal lengths $+10\, cm$ and $-10\, cm$ respectively. State the nature and power of each lens. Which of the two lenses will form a virtual and magnified image of an object placed $8\, cm$ from the lens? Draw a ray diagram to justify your answer.

When an object is placed beyond the center of curvature $(C)$ in front of a concave mirror,where is the image formed and what is its nature?