Define power of a lens. What is its unit?

Important Questions on Light - Reflection and Refraction

MEDIUM

10th CBSE

IMPORTANT

Eduwiser's CBSE PHYSICS FOR CLASS X>Chapter 4 - Light - Reflection and Refraction>EXERCISE>Q 7

If the power of a lens is $+ 2.0 \mathrm{D}$, what does it imply?

EASY

10th CBSE

IMPORTANT

Eduwiser's CBSE PHYSICS FOR CLASS X>Chapter 4 - Light - Reflection and Refraction>EXERCISE>Q 7

Calculate the power of a lens of focal length $- 10 \mathrm{cm}$. What is the nature of lens?

MEDIUM

10th CBSE

IMPORTANT

Eduwiser's CBSE PHYSICS FOR CLASS X>Chapter 4 - Light - Reflection and Refraction>EXERCISE>Q 7

If a convex lens of focal length $10 \mathrm{cm}$ and a concave lens of focal length $20 \mathrm{cm}$ are kept in contact with each other, what is the focal length of the combination?

EASY

10th CBSE

IMPORTANT

Eduwiser's CBSE PHYSICS FOR CLASS X>Chapter 4 - Light - Reflection and Refraction>EXERCISE>Q 1

The speed of light in air is

EASY

10th CBSE

IMPORTANT

Eduwiser's CBSE PHYSICS FOR CLASS X>Chapter 4 - Light - Reflection and Refraction>EXERCISE>Q 2

A ray of light travelling in air enters water. The angle of refraction will be

EASY

10th CBSE

IMPORTANT

Eduwiser's CBSE PHYSICS FOR CLASS X>Chapter 4 - Light - Reflection and Refraction>EXERCISE>Q 3

A ray of light passes undeviated at the interface of two media. The angle of refraction must be

EASY

10th CBSE

IMPORTANT

Eduwiser's CBSE PHYSICS FOR CLASS X>Chapter 4 - Light - Reflection and Refraction>EXERCISE>Q 4

A ray of light travelling in air is incident on the surface of a rectangular  plastic slab of refractive index $\sqrt{2}$. If the angle of refraction is $30°$, what is the angle of incidence?

EASY

10th CBSE

IMPORTANT

Eduwiser's CBSE PHYSICS FOR CLASS X>Chapter 4 - Light - Reflection and Refraction>EXERCISE>Q 5

The speed of light in a given medium is $2.5\times {10}^8 \mathrm{m}/\mathrm{s}$. If the speed of light in air is $3\times {10}^8 \mathrm{m}/\mathrm{s}$, what is the refractive index of the given medium?