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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
What is the power of a lens with a focal length of 0.5 meters?
💡 Hint: Use the formula P = 1/f.
Question 2
Easy
A concave lens has a focal length of -0.5 m. What is its power?
💡 Hint: Similar formula applies for negative focal lengths.
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 unit of power for a lens?
- Meters
- Diopters
- Amperes
💡 Hint: Think of the formula involving focal length.
Question 2
True or False: A concave lens has positive power.
- True
- False
💡 Hint: Remember the relationships between lens types and their power.
Solve and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
Calculate the power of a lens with a focal length of 15 cm. What if the same lens is now submerged in water with a refractive index of 1.33?
💡 Hint: Don't forget to apply the refractive index when submerged!
Question 2
An optician has both a -4D and a +5D lens. What type of lens system can she create, and what will be the resulting power?
💡 Hint: Addition of powers: Practicing it makes perfect!
Challenge and get performance evaluation