VR Tour For Std. 7 Chap 15: Light
What's Included in Virtual tour of this chapter
Light is a form of energy that enables us to see all the things around us. The main source of light on the earth is the sun. Plants are able to prepare their own food using sunlight. Some other objects also give out light. We will also learn about two types of spherical mirrors: Concave Mirror and Convex Mirror. Further in the chapter we will also understand how the reflection takes place in concave and convex mirrors and the laws of reflection. We will also unmask the reason for how the rainbow is made.
Virtual tour 1: Light travels along a straight line
Light travels from one place to another in a straight line. When we try to pass light rays through the straight pipe, it is passed, but when we try to pass the light through the little bent pipe, it is not passed. So we can say that the light travels in the straightway. We will understand this through an experiment.
Virtual tour 2: Uses of the concave mirror
A concave mirror can form a real and inverted image. When the object is placed very close to the mirror, the image formed is virtual, erect and magnified. In the concave mirror the reflecting surface is curved inwards. A concave mirror is used in various places. And one of them is a solar cooker. Let’s explore this in our virtual activity.
Virtual tour 3: Uses of convex mirror
A convex mirror is a curved mirror for which the reflective surface bulges out towards the light source.Convex mirrors are commonly used as rear-view mirrors in vehicles because they give an erect, virtual, full size diminished image of distant objects with a wider field of view and it covers a wider angle than the flat mirror.
Virtual tour 4: The Newton's Disc: The Disappearing Colour Disc
Everybody knows that the rainbow consists of seven colors which we commonly refer to as VIBGYOR. Do you ever wonder how a rainbow is made? The white light of the sun contains seven-colored lights in it that separate out due to refraction. This is called a Spectrum of Lights. This spectrum of white light can be seen in the rainbow, soap bubbles, surface of a CD and prisms.
Virtual tour 5: Refraction of light by convex lens and concave lens
When the light rays pass through the convex lens, it converges the light rays and focuses on one point. On the other hand, when the light rays go through the concave lens, it diverges the beams, i.e. they spread out.
Virtual tour 6: Laws of reflection of light
The law of reflection states that, the angle of incidence is equal to the angle of reflection. So, in this virtual activity, we will explore that when torchlight strikes on the mirror, It reflects back in a particular direction.