Refrigerators are like rockets, right?

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    Refrigerators Rockets
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SUMMARY

The discussion centers on the physics of refrigerators and their heat dissipation mechanisms, comparing them to rockets. It establishes that the heat generated by a refrigerator's coils does not produce significant recoil due to the negligible momentum loss, which is insufficient to overcome friction. The conversation also delves into the mechanics of a ballistic pendulum, emphasizing that the inelastic collision of a bullet with the pendulum results in a substantial loss of kinetic energy, quantified at 99.7 percent. Participants clarify that while heat is molecular motion, its dissipation does not impart enough momentum to affect the refrigerator's stability.

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  • #31
It can be. It's just not very efficient propulsion.

Maybe a flashlight is like a roman candle.
 
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  • #32
brainstorm said:
If radiation/light/infrared has momentum, why can't it be a source of propulsion without ejecting any kind of particle matter?
It can be - it just doesn't provide very much (as I discussed earlier).
 
  • #33
Antiphon said:
It can be. It's just not very efficient propulsion.

Maybe a flashlight is like a roman candle.

Maybe a roman candle is like a sparkler scaring away fireflies. These absurd analogies are fun. I think a whole section of the forum should be devoted to them. It would be like youtube without the videos.
 
  • #34
Antiphon said:
Maybe a flashlight is like a roman candle.
It is. In principle.
 
  • #35
DaveC426913 said:
It is. In principle.

Why, because they both send out discrete packages of luminosity that require chemical propellant to achieve subsonic velocity and then fade away after @50ft?

Or because they're both cylindrical and produce illumination?
 
  • #36
brainstorm said:
Why, because they both send out discrete packages of luminosity that require chemical propellant to achieve subsonic velocity and then fade away after @50ft?

Or because they're both cylindrical and produce illumination?

Because both produce thrust.
 
  • #37
DaveC426913 said:
Because both produce thrust.

Ok, let's assume you were trying to come up with a propulsion system that uses EM radiation. Obviously you want it as efficient as possible in terms of unit energy to unit propulsion. What would the variable parameters be for waste? Would there be certain wavelengths that would generate more thrust than others?
 
  • #38
brainstorm said:
Ok, let's assume you were trying to come up with a propulsion system that uses EM radiation. Obviously you want it as efficient as possible in terms of unit energy to unit propulsion. What would the variable parameters be for waste? Would there be certain wavelengths that would generate more thrust than others?

My post 34 consists of exactly 4 words. Of those 4 words, it seems I have the need to repeat two of them:

In principle.

:wink:
 

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