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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
What is the lens formula?
💡 Hint: Think of the relation between focal length, image distance, and object distance.
Question 2
Easy
How do you determine if an image is real or virtual?
💡 Hint: Recall the sign convention.
Practice 4 more questions and get performance evaluation
Interactive Quizzes
Engage in quick quizzes to reinforce what you've learned and check your comprehension.
Question 1
What does the lens formula relate?
- Focal length to object distance
- Image distance to object distance
- All of the above
💡 Hint: Consider all elements involved.
Question 2
True or False: The image distance in a concave lens is always positive.
- True
- False
💡 Hint: Refer to the definitions of real and virtual images.
Solve 1 more question and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
A convex lens has a focal length of 15 cm. An object is placed 20 cm from the lens. Find the image distance and describe the nature of the image.
💡 Hint: Carefully substitute values into the lens formula and evaluate.
Question 2
If a concave lens forms a virtual image of an object at 10 cm, and the focal length is -5 cm, determine the object distance.
💡 Hint: Use the lens formula carefully to derive the object distance.
Challenge and get performance evaluation