# Twice the speed of light.

Discussion in 'Physics & Math' started by Beaconator, Jul 18, 2021.

1. ### QuarkHeadRemedial Math StudentValued Senior Member

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Proof required

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3. ### SsssssssRegistered Senior Member

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See any relativity textbook.

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5. ### Write4UValued Senior Member

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An explosion is non-zero energy!

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7. ### dart_shipRegistered Member

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then, Write4U, an object of mass would explode.

8. ### SsssssssRegistered Senior Member

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What is exploding and what are the products and what are you counting as part of the explosion and what not?

9. ### DaveC426913Valued Senior Member

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Dart, you're new here so you're entitled to some catching up time.
But if you want to be understood, it's really important that you learn to use the quote feature. It is not at all clear to whom these snippets of responses are directed.

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10. ### dart_shipRegistered Member

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an explosion is an element reaching boiling point (becoming a gas) without a release for it Ssssssss.

11. ### SsssssssRegistered Senior Member

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Not in general it isn't but in that particular case everything has mass.

12. ### dart_shipRegistered Member

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okay DaveC426913.

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13. ### dart_shipRegistered Member

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Ssssssss can you name something that does not have mass?

14. ### SsssssssRegistered Senior Member

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Light in vacuum.

15. ### dart_shipRegistered Member

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do all elements exist in a state of either solid, liquid or gas (heating or cooling changes their state)?

16. ### dart_shipRegistered Member

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could light in a vacuum reflect off objects Ssssssss?

17. ### SsssssssRegistered Senior Member

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I don't know. If only there was a 3,500km diameter lump of rock up in space where we could see if the Sun's light might reflect off it...

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18. ### dart_shipRegistered Member

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Ssssssss would an object of zero mass pass through an object of mass?

19. ### DaveC426913Valued Senior Member

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:looks out his workshop's transparent glass window, thoughtfully pondering dart's question, while working on his X-ray machine and listening to his radio:

20. ### Write4UValued Senior Member

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https://www.desy.de/user/projects/Physics/Relativity/SR/light_mass.html#

But IMO, light has mass. A photon at rest has zero mass. A photon in motion @ c acquires mass, i.e. "energy and momentum" = mass

21. ### Write4UValued Senior Member

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How about a super nova?
If sufficiently stimulated an object of mass does explode. A nuclear device has mass that explodes atom by atom after the nuclear process has been activated by inward pressure.

22. ### SsssssssRegistered Senior Member

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You really don't understand the first thing about this do you. Get a textbook.

23. ### Write4UValued Senior Member

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E = Mc^2
Question: does a photon @ c have energy?

A photon @ c has energy (E). Therefore a photon @ c acquires the equivalent energy as a massive particle would at a lower speed.