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Breakthrough Junior Challenge
Course: Breakthrough Junior Challenge > Unit 1
Lesson 3: 2015 Challenge — Physics- Special theory of relativity - 2015 Challenge Winner!
- A visualization of special relativity
- Chromatic aberration
- Orbital mechanics
- What is light?
- Special and general relativity
- The science of fireworks
- Quantum tunneling
- Antimatter
- Special Relativity
- What Einstein missed: The EPR paradox
- Virtual particles and gravity
- Interstellar and Hawking radiation
- All about superconductors
- Entropy and the direction of time
- Magnetism, light and the magneto optic Kerr effect
- The theory of everything
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What is light?
By Keeley Hoek
What is light? Light is fundamental to our interaction with the natural world, and yet what it really is remains a mystery to many. The answer is incredible.
What is light? Light is fundamental to our interaction with the natural world, and yet what it really is remains a mystery to many. The answer is incredible.
Want to join the conversation?
How sun is producing light?(3 votes)
I do not understand it completely, but this link may be helpful:
http://curious.astro.cornell.edu/our-solar-system/137-physics/general-physics/particles-and-quantum-physics/805-how-are-photons-created-and-destroyed-advanced(3 votes)
If light some light comes into our eyes how is it possible for us to see at night or mid - night how does it really work?(1 vote)
We always need light to see. Our eyes can adjust so we only need a little amount of light, but we still need it. Animals that can "see in the dark" actually can't. They are just able to absorb more light than us.(3 votes)
how can we find the direction the arrow will point and at6:14how can we be sure only 1 line will pass the segment .(1 vote)
So when we talk about the speed of light , are we talking about the speed of photon?(0 votes)
Does photon has any mass? If yes, though it would have a less mass its momentum would be very high due to its speed. So i would get a lot of hurt. So can i say photons are mass less.
But i read somewhere that light bends somewhat by gravity but unnoticable.So it must have mass.
These bot are contradiction.Can you please help me with answer about photons mass.(1 vote)
Photons DO NOT have mass! They are completely massless because they can travel at the speed of causality. They also experience their entire existance in an instant. This is not possible for particles with mass. Also, photons are their own antiparticle. They ride the spacetime sea like massless ships. The curves affect the photon just like any other particle, just the photon is moving at the top possible speed for any particle; the speed of a massless one.(0 votes)
6:14