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[Sirus]

My crappy laptop can run it...barely. It's only a dual-core 2.3 Ghz processor and no real graphics card, but it will at least run using medium-sized rockets on minimum settings.

[ank]

I was also under the impression that light was more of a wave than a particle and thus might appear to have mass without actually having any. Also I learn my theoretical physics from the internet, so don't mind me.

Light is BOTH a wave and a particle... called wave/participle duality. This is most likely the most annoying part of physics.
And it gets worse, because any quantum sized particle works this way.
You can do experiments to show that both light and electrons are waves(the double slit experiment), but you can also do an experiment that shows that they are both particles.
I bet you many a physicist has gone insane thinking about this.

And no, light does not have momentum.
Momentum is giving by the equation:
P(momenta)=Mass * velocity.
or
E=½mv^2

in both equations we can see that if Mass is zero, then P and E will also be zero.

!! Math !!

I hope this redeems me of my stupid comments about Nuclear-Thermal drives.

[RulerOfNothing]

I was also under the impression that light was more of a wave than a particle and thus might appear to have mass without actually having any. Also I learn my theoretical physics from the internet, so don't mind me.

Light is BOTH a wave and a particle... called wave/participle duality. This is most likely the most annoying part of physics.
And it gets worse, because any quantum sized particle works this way.
You can do experiments to show that both light and electrons are waves(the double slit experiment), but you can also do an experiment that shows that they are both particles.
I bet you many a physicist has gone insane thinking about this.

And no, light does not have momentum.
Momentum is giving by the equation:
P(momenta)=Mass * velocity.
or
E=½mv^2

in both equations we can see that if Mass is zero, then P and E will also be zero.

!! Math !!

I hope this redeems me of my stupid comments about Nuclear-Thermal drives.

Unfortunately this would mean that photons of light do not have any energy. You are unfortunately still not redeemed . The problem here is that you used the Newtonian formulas for kinetic energy and momentum. Quantum theory says that photons have a finite and non-zero energy and momentum, equal to h*c/wavelength and h/wavelength respectively (where h is Planck's constant).

[LoSboccacc]

And no, light does not have momentum.
Momentum is giving by the equation:
P(momenta)=Mass * velocity.

yes it does.
strawman: momentless photons would be instantly deflected by gravity, instead of gradually, so gravitational lenses would not work.

momentum: p = h / λ

[ank]

I was not talking about energy in a light wave, i was talking about momentum of a light wave.
and the other equation was the kinetic energy.
as you point out you need a third equation to determine the amount of energy in a lightwave.

I was trying to prove with mass that photons does not have momentum, because they do not have mass, which is still very true.

Saying that this means light has no energy is true, if energy is only momentum. however it is not. energy takes many many forms.
You wouldn't say that the chemical energy in a chocolate bar is momentum either?

The first equation relates to the energy of a photon, which is not what we are discussing.
so I went searching for the second equation I found this on wikipedia:

For both massive and massless objects, relativistic momentum is related to the de Broglie wavelength λ by

    p = h/\lambda\,,

Electromagnetic radiation (including visible light, ultraviolet light, and radio waves) is carried by photons. Even though photons (the particle aspect of light) have no mass, they still carry momentum. This leads to applications such as the solar sail.

I sure love when things come full circle!

I am still sticking to my first point though: Photons have no mass.(which you would agree with)

Also measuring light in Newtons seems weird, but I guess thats science for you 

[sneakey pete]

It doesn't really matter anyway. Right now this part is just a very efficient low thrust engine that uses standard fuel. With the word nuclear tacked on to it for some kind of explanation.

[Putnam]

wave/participle duality.

Why, it's both surf AND surfing!

[LoSboccacc]

it is intended for space navigation: it has a higher efficiency in void than other engines.


enough with this dual wave particle heresy. everyone knows that kerbal fuel tanks are filled with phlogiston

[Sirus]

And everything is built of explodium.

[Rose]

This makes water landings, no matter how gentle, impossible.

[Techhead]

I was not talking about energy in a light wave, i was talking about momentum of a light wave.
and the other equation was the kinetic energy.
as you point out you need a third equation to determine the amount of energy in a lightwave.

I was trying to prove with mass that photons does not have momentum, because they do not have mass, which is still very true.

Saying that this means light has no energy is true, if energy is only momentum. however it is not. energy takes many many forms.
You wouldn't say that the chemical energy in a chocolate bar is momentum either?

The first equation relates to the energy of a photon, which is not what we are discussing.
so I went searching for the second equation I found this on wikipedia:

For both massive and massless objects, relativistic momentum is related to the de Broglie wavelength λ by

    p = h/\lambda\,,

Electromagnetic radiation (including visible light, ultraviolet light, and radio waves) is carried by photons. Even though photons (the particle aspect of light) have no mass, they still carry momentum. This leads to applications such as the solar sail.

I sure love when things come full circle!

I am still sticking to my first point though: Photons have no mass.(which you would agree with)

Also measuring light in Newtons seems weird, but I guess thats science for you 

Photons have no rest mass (aka invariant mass). All of your posts used Newtonian equations, which don't really cut it when dealing with things that move at the speed of light (or significant fractions thereof). Try including the Lorentz factor and see if that changes things.

[Rose]

So who else misses the old parts?

[LoSboccacc]

Me! Me!

Also, the silisko pack and the nova punch.

They made for really good looking rockets.

[Rose]

This thing with 3-person pods being huge annoys me.

[LoSboccacc]

not the other thing about them being fugly? (hugeness can be cured by 2x power 0.5 fuel consumption on engines )