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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
What is the sign of the focal length for a convex lens?
💡 Hint: Remember the behavior of light with convex lenses.
Question 2
Easy
What does it mean if an object is located at -15 cm from the optical center?
💡 Hint: Think about the direction of measurements.
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 focal length of a convex lens?
- Positive
- Negative
- Zero
💡 Hint: Think about how the lens focuses light.
Question 2
A concave lens has a focal length of -15 cm. Is this lens diverging or converging?
- Diverging
- Converging
💡 Hint: Recall the characteristics of concave lenses.
Solve 1 more question and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
A concave lens produces a virtual image at 4 cm from the lens when the object is placed at 6 cm. Calculate the focal length.
💡 Hint: Don’t forget the signs when substituting values!
Question 2
Given a convex lens with a focal length of +20 cm, determine the image distance for an object placed at +30 cm.
💡 Hint: Pay attention to where each measurement is taken from.
Challenge and get performance evaluation