Power of Lens
Physics ⇒ Light and Optics
Power of Lens starts at 10 and continues till grade 12.
QuestionsToday has an evolving set of questions to continuously challenge students so that their knowledge grows in Power of Lens.
How you perform is determined by your score and the time you take.
When you play a quiz, your answers are evaluated in concept instead of actual words and definitions used.
See sample questions for grade 12
A combination of two lenses has a net power of 0 D. If one lens has a power of +3 D, what is the power of the other lens?
A convex lens and a concave lens, each of focal length 20 cm, are placed in contact. What is the net power of the combination?
A lens has a focal length of 25 cm. What is its power in dioptres?
A lens has a focal length of -50 cm. What is its power in dioptres?
A lens has a power of +0.5 D. What is its focal length in meters?
A lens has a power of +5 D. What is its focal length in centimeters?
A lens has a power of -4 D. Is it a converging or diverging lens?
A lens has a power of -8 D. What is its focal length in centimeters?
A person needs a lens of power +2.5 D for reading. What is the focal length of the lens in meters?
A student uses a lens of power -2 D to correct his vision. What is the focal length of the lens in meters?
Define the power of a lens and state its SI unit.
Describe how the power of a lens is related to its ability to converge or diverge light.
Explain the significance of the sign of the power of a lens.
Explain why the power of a concave lens is always negative.
Explain why the power of a lens changes when it is immersed in a medium other than air.
If a lens has a focal length of 0.5 m, what is its power?
If a lens has a focal length of 10 cm, what is its power in dioptres?
If a lens has a power of +10 D, what type of lens is it?
If the focal length of a lens is doubled, what happens to its power?
If the power of a lens is zero, what can you say about its focal length?
