Practice Power Of A Lens (p) (6.2.3.4) - Optics

Practise this section

10 questions

Flashcard drill
3 cards from this section. Quick, good the night before a test.
Exercise
6 questions · about 4 min · pass mark 70%. Hints available.
Sign up to start the exercise
Quiz
4 questions · about 3 min · pass mark 70%. Hints available.
Sign up to start the quiz

6 sample questions

Question 1.
What is the formula for the power of a lens?
Show hintHide hint
Think of how lens power relates to focal length.
Question 2.
Is the power of a convex lens positive or negative?
Show hintHide hint
Remember: convex lenses converge light.
3Question 3.
What does the power of a lens indicate?
- How much it can expand light
- How strongly it converges or diverges light
- The thickness of the lens
Show hintHide hint
Think about the effects of lenses on light.
4Question 4.
A concave lens has a power of -2.5D. What is its focal length?
Show hintHide hint
Use the lens power formula.
Question 5.
A lens has a focal length of 30 cm. If combined with a concave lens of -10D, what is its total power?
Show hintHide hint
Remember to use the power of both lenses in the calculation.
Question 6.
In a camera, a lens with a power of +5D is used. Calculate the required focal length for clear image capture.
Show hintHide hint
Use the formula relating power to focal length.

6 more questions in this section. Enroll free to practise them all.