1. What is the focal length of a convex lens if parallel rays of light converge at a point 25 cm away from the lens?

2. A concave mirror produces a real image that is three times larger than the object. If the object is placed 10 cm in front of the mirror, what is the mirror's focal length?

3. If an object is placed between a convex lens and its focal point, the image formed will be:

4. A concave mirror has a focal length of 20 cm. An object is placed 40 cm in front of the mirror. Where is the image located?

5. What is the image distance for an object located at the focal point of a convex lens?

6. A concave lens always forms an image that is:

7. What is the result of placing an object at twice the focal length from a convex lens?

8. If the magnification of a concave mirror is -2, what can be inferred about the image?

9. For a convex mirror, if the radius of curvature is 30 cm, what is the focal length?

10. An object is placed 60 cm in front of a convex lens of focal length 20 cm. What is the nature of the image formed?