What are your favourite physics/mathematics misconceptions?

  • #71
fresh_42
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As a kid, I thought we could get rid of our nuclear waste by shooting it into the sun only using the sun's gravity. Now I know, that this plan has a little momentum problem. But on the other hand, I have a new idea: why not use the waste for generating electric energy for a small magnetic field so that the radiation can be turned into an ion thruster?
 
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  • #72
ergospherical
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Better yet - if you have a Kerr black hole handy...

1638582177134.png


1638582192299.png


Source: MTW.
 
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  • #73
Frabjous
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As a kid, I thought we could get rid of our nuclear waste by shooting it into the sun only using the sun's gravity. Now I know, that this plan has a little momentum problem. But on the other hand, I have a new idea: why not use the waste for generating electric energy for a small magnetic field so that the radiation can be turned into an ion thruster?
I actually saw a presentation about launching waste into orbit in the late nineties. If memory serves, putting the stuff in an orbit inside of Venus is “reasonable.” The big problem is Earth’s gravity well. Large amounts in a single launch has safety problems in case things go wrong. The proposal I saw proposed launching small volumes to get around this. Another issues is getting the material to a launch site. A lot of the waste is a sludge in decaying barrels. The total amount is extremely large in the context of moving or “processing” it for launch.
 
  • #74
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This only happens to famous skeletons, and only if someone who is alive starts it!
Newton would rotate in his grave.
What kind of angular momentum would he have?
 
  • #75
fresh_42
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What kind of angular momentum would he have?
About 2 Nms.
 

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