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r/dresdenfiles•
Tellurion

Harry And Physics

Harry has long been thinking about Physics and the way it relates to magic, that is the physical effects that magic can generate, such as taking heat from one place and putting it somewhere else to create a refrigeration effect.

What else could he do? What about using a Forzare variant to remove the momentum from an opponent, for example transferring it to something else. Subtracting the rotational speed of the Earth from someone, have them effectively flying backwards at up to 1070 mph (at the equator) less elsewhere. Not unlike Harry's Earth attack. You would need to put the energy somewhere though, could he speed up half of someone's body and slow down the other half? It might be a type of attack that no one has figured a defence against, having two halves of ones body accelerate away in different directions at 1,000 mph. "Forcipe!" would work as a name for such a spell.

Any other ideas?

Posted Sep 8, 2014, 1:38 PM UTC · edited

521
PotentiallySarcastic•

I'd say that your method would probably require him to draw from a ley line like in Changes. To draw motion from the Earth as a whole would require a lot of energy. Sure he could do it, but it would require a ton of muscle and time.

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BlackStar4•

Was about to say this. In order to remove the kinetic energy granted by Earth's rotation (for this calculation, approximated at 1000 mph) from an average (88.3 kg) man, he would have to remove 8823.1 KJ of energy. That's about equal to 2.1 kg of TNT. That energy has to go somewhere, and since Harry is not the best at fine control (and this is Jim we're talking about) it's going to either go into him, or make the surrounding area go kablowie.

EDIT- that amount of energy is just over 2000 kcal. Harry could pull this one off without a ley line, but he's only gonna have the one shot.

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TheAmazingBunbury•

Seems like it could be used for Harry's last-ditch-before-I-pass-out-dramatically move.

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BlackStar4•

This is assuming every last bit of power is transferred 100% efficiently though. Harry is many things, but efficient with his power is not one of them.

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TheAmazingBunbury•

He's actually getting there, I think. He has improved in his fine control and his raw power since the series began. He went through the whole "teaching the apprentice forced me to relearn the basics" thing, and it helped with his control. Then he went through Mab Boot Camp and it forced him to think outside the box and improvise.

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Anubissama•

Well he isn't effective at using his own power efficiently BUT he always sad that redirecting currents of energy is one of his talents.

1
TellurionOP•

No you just withdraw the relative motion for the person involved, not the Earth. The Earth keeps moving unchanged, the person doesn't.

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BlackStar4•

He has to remove that amount of energy though, and it has to go somewhere. Also, moving that kind of power around can't be easy on his mind- remember when he channeled the storm in Storm Front?

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EdgeOfDreams•

If you want to see more magic that works off of these kinds of physics, I highly recommend the book "Name of the Wind" by Patrick Rothfuss. The "sympathy" magic in that series works by making links between objects and then transferring energy between them. The more similar the objects, the more efficient the energy transfer will be.

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TellurionOP•

That actually sounds like the classical magical law of similarity, physicists would call it quantum entanglement.

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EdgeOfDreams•

Yeah, it's very grounded in both traditional ideas of magic and modern physics.

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phykicks•

He's seen better bullet protection on the cloaks of the grey council, and we've seen him store kinetic energy in his rings before. I want to see him link his leather duster and rings together to be able to stop bullets, store their energy in his rings. The drawback would have to be the limit to how much the ring could store of course. So if taking tons of fire he'd have to be flinging out tons of kinetic blasts as well or else the rings would explode or the protection would fail, then bullets go through his duster.

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Bakoro•

If he had that spell to instantly stop someone's motion (from outside their own reference frame, he'd always have to be aware of what direction he's facing. Imagine having a fat monster fly right at you at 1000 mph. That'd be a terrifying millisecond.

There's also speculation that the galaxy is moving through space at a speed of 2,237,000 MPH. Stopping someone dead from the Universes' perspective would put them out in the middle of space before they realized what's happening.

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Thanatos17901•

Even at the Earth reference, that sort of acceleration should cause air resistance to turn a thing into a fine mist pretty instantly

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FreIus•

I think this may start to become relevant.
Yes, the galaxy moves at a little more than a third of the speed in that "What If", but I guess some effects may still take place.

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FelixTKatt•

How about this: a push-pull force spell. It starts with a small amplitude, long waveform - but sets up a standing wave with constructive interference. Then, by pumping in a steady amount of power, the amplitude increases until -- well, ever hear of Bucking Betty? or the San Andreas fault?

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mandoimissmst3k•

in one of the stories in side jobs, he minimized gravity for most of an area to concentrate it on black court vamps to basically pudding them up. not far from what you're talking about.

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Frommerman•

That was Changes.

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mandoimissmst3k•

it was also in It's My Birthday, Too.

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FelixTKatt•

What if he reversed this? Slightly increased gravity in a large area to create a localized anti-grav. field. He could leap tall buildings in a single bound! PARKOUR!

3