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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
What is the principal axis of a lens?
💡 Hint: Think about what line helps us track light behavior.
Question 2
Easy
Define the optical center of a lens.
💡 Hint: This point is like an 'open door' for light.
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 is the principal axis of a lens?
- Line through the lens center
- Line at 90 degrees
- A curved line
💡 Hint: Think about how light interacts with the lens.
Question 2
True or False: The optical center is where rays deviate when passing through a lens.
- True
- False
💡 Hint: Recall the definition of the optical center.
Solve 1 more question and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
If a convex lens has a focal length of 15 cm, at what distance from the lens will a parallel ray converge?
💡 Hint: Recall how focal lengths dictate convergence points.
Question 2
A concave lens has a focal length of -20 cm. Where do light rays appear to come from if they enter parallel to the principal axis?
💡 Hint: Keep in mind the sign convention for concave lenses.
Challenge and get performance evaluation