Wikipedia

Search results

Showing posts with label Physics lessons online for student. Show all posts
Showing posts with label Physics lessons online for student. Show all posts

Wednesday, 5 April 2017

What is light for all


 Dual nature of Light  

(a) Particle   (b) Wave


Light has dual nature particle (photon) as well as wave.

 

What is Photon. Photon is define as, very very tiny (smallest) particle/packet of energy. The rest mass of photon is zero.
 

What is wave. Wave is define as, A wave can be described as a disturbance that travels through a medium from one location to another location.
 

 

Albert Einstein's photoelectric effect experiment proves that light can behave as a particle while 

 

Thomas Young's double-slit experiment shows that it also behaves as a wave.
 

Albert Einstein proved that in 1905, light could behave as a particle by showing that a beam of light could eject electrons from metal when a suitable radiation (invisible ray) fall on metal, This suggested that light consisted of photons that could eject electrons of similar frequency. Einstein's discovery altered the prevalent theory at the time, which held that light was only a wave.
 

And light has the wave nature also, it has proved earlier by Young in 1801. In his experiment, Young shone light between two parallel slits, causing the light waves to interfere with each other and form a patter of dark and light bands. If light was primarily a particle, it would have formed two parallel lines.
 

Quantum mechanics explains the duality of light by describing it as a wave-packet. A wave-packet refers to waves that may interact either as spatially localized, acting as particle, or interacting like waves. This means light photons can either act as a particle or wave, depending on the circumstances.

 

Wave, electromagnetic wave, wave example
Making wave by rope


Making wave by water


Wave, electromagnetic wave, wave example
Wave example


Wave, electromagnetic wave, wave example
Electromagnetic wave


electromagnetic wave
Electromagnetic wave


Wave, electromagnetic wave, wave example
Wave details



Wave, electromagnetic wave, wave example
Wave example


Wave, electromagnetic wave, wave example
Electromagnetic wave


Wave, electromagnetic wave, wave example
Electromagnetic wave


Tuesday, 28 March 2017

Sun radiation facts

 

The Sun Lights

 

The actual color of sun's light is white. When astronauts see the sun from space its look white.

Why its looks like white, because its light is not scattered by atmosphere.

And white color is mixture of seven colors called VIBGYOR.

But we can not see all color by our naked eyes, to watch VIBGYOR we will have to pass the sun's light through Prism or water's drops.

But there are some animals who can see all color of VIBGYOR as well as ultraviolet lights also with their naked eyes. e.g, honey bees can see ultraviolet lights, Pit viper can see infrared, Puppies, meanwhile can see into our heart, frogs can detect very sensitive photons.

Why leafs looks green, because leafs reflects only green color from VIBGYOR, and absorbed left all colors.

 

pit viper snake
Pit viper snake



prism
When light passing through a prism

bee
Honey bee can also see U.V radiation


rainbow
Rainbow


frog
This frog can see U.V light


prism
When sunlight passing through the prism


water bubble
Water bubble with rainbow color


Friday, 24 March 2017

Physics lessons online for student

Lets know about Light.


Study of light is called optic.

Light travels in straight path

Light has electromagnetic energy.

Generally there are two type of light, (a) Visible light (b) Invisible light.

When we talk about visible light is known as light or optic. e.g, Sun light.

When we talk about invisible light is called electromagnetic radiation,  e.g, ultraviolet radiation

Light is made by very tiny packets called photon.

Every photons contain lots of energy.

Speed of light changes with change of mediums (objects or materials).

 

light and shadow
Light


light and shadow
Light and its components


light and shadow
When light passing through the prism


Lets know about Shadows.


99.99% Space is dark (full of shadows).

Because there is no sufficient light, light is visible when it has an object in its path.

No one has seen the shadow of moon, sun, Jupiter, mars, earth, Venus etc in space.

There is no shadow of astronauts has found in moon.

In ancient time people was thinking about shadow formed by sun, thought lot and utilized this principle in making the world’s most primitive clocks, the sundials.

 

light and shadow
Light and shadow combination


light and shadow
shadow and light combination


light and shadow
Earth from space