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Unit 1: Light – reflection & refraction (Hindi)

1,700 possible mastery points

About this unit

When light travels from one medium to another (like air to glass, or glass to water), it does three things. Some of it bounces off, some of it goes through, and the rest of it is absorbed. In this chapter, we will explore the first two. We will explore what rules govern them, their technical names and then apply these rules to study the beautiful world of curved mirrors and lenses.
We see light bouncing all around us. It makes us see most of the things. In this lesson, we will explore the rule that this 'bouncing' of light obeys and talk about plane mirrors.
We have experience and intuition for flat mirrors. But if we slightly curve these mirrors, a whole new world opens up. In this lesson we will explore the concave and convex mirrors and their applications.
Let's learn how to construct images, when an object is kept in front of curved mirrors, using ray diagrams.

Practice

It's possible to address whether a mirror is concave or convex, whether an object is in front or behind the mirror, whether an image is real or virtual, with just positive and negative signs. Let's explore how in this lesson
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let's see if we can figure out where an image would be, given where an object is kept in front of a curved mirror. In effect, we will end up deriving the famous mirror formula.
Let's explore how to use the mirror formula to locate image positions when objects are kept in front of convex and concave mirrors.
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You may have seen that a straw, immersed in a glass of water, appears bent. It's actually the light, coming from the straw, that's bent. Light bends when it changes medium. It's a big deal because if it didn't, our eyes wouldn't work. So let's explore this bending of light in this lesson.
In this lesson, we will clarify the difference between absolute & relative refractive index. We will also see how to connect them.
Let's explore how to construct images, when objects are kept in front of a lens, by drawing ray diagrams.
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Given the object location and focal length of a lens, let's figure out exactly where the image would be. We will be deriving the lens formula & magnification formula for lenses.
Let's explore how to use the lens formula to figure out where images are and how big they get when some objects are kept in front of lenses.
You may have heard about power related to your eye after a typical eye exam. Let's explore what this 'power' is and why define them that way.

Practice

Level up on the above skills and collect up to 320 Mastery points
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Unit test

Level up on all the skills in this unit and collect up to 1700 Mastery points!