Formation of Rainbow / How Rainbow is formed

Rainbow            When sunlight enters a raindrop, it is refracted along its path, causing different wavelengths of white light. So the one with higher wavelength (red) bends the least while the one with lower wavelength (violet) bends the most. After this, these component rays hit the surface inside the drop and … Read more

Refraction of light class 10 physics

Refraction of light

When a ray of light enters from one transparent medium to another transparent medium, it deviates from its straight path, this phenomenon is called refraction of light.
 

Or,

When a ray of light enters from a rarer medium to a denser medium, it bends towards the normal. Similarly, when a ray of light enters from a denser medium to a rarer medium, it deviates away from the normal, which we call refraction of light.
(Dense = dense, rarer = less dense)
 

Law of refraction

This rule is also called Snell’s law.
Snell propounded the following laws of refraction through experiments:
 
 
 1. The incident ray, the refracted ray and the normal to the refracting surface at the point of incidence, all three lie in the same plane.
 
 2. For any transparent medium pair, the ratio of sine of the angle of incidence and sine of the angle of refraction is a constant.
 
 The angle of incidence (i) and angle of refraction (r) are the angles that the incident ray and the refracted ray make with the normal respectively.
 
 Therefore,
 
Refractive index of a medium =
Speed of light in vacuum/speed of light in medium
 
n = sin i / sin r
Where,
n is a constant, which is called the refractive index of the second medium with respect to the first medium.

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Refraction by lens class 10 physics

Refraction by lens A transparent medium surrounded by two curved surfaces, one or both of whose surfaces are spherical, is called a lens. There are two types of lenses- 1. convex 2. concave Convex lens   The two spherical surfaces protruding outward in a lens are called convex lenses. Convex lens thicker in the middle … Read more

Reflection of light class 10 physics

Reflection of light   When a traveling ray of light hits a reflective surface, it returns back to the same medium or gets reflected, then this phenomenon is called reflection of light. Law of reflection There are two laws of the reflection of light, 1. An angle of incidence is equal to angle of reflection. … Read more

Why sky is blue in colour | What is Scattering of light

SCATTERING OF LIGHT   When the sunlight travels in the Earth’s circle, it is scattered by the particles in the atmosphere. Light of shorter wavelengths is far more visible than that of larger wavelengths. The amount of scattering is inversely proportional to the 4th power of wavelength. (This is called Raleigh scattering.) This is why … Read more