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Heat shields?

  1. Jan 9, 2007 #1
    1. The problem statement, all variables and given/known data
    Crewed spacecraft are equipped with heat shields for protection when they re-enter the Earth's atomsphere. Why is this necessary?

    2. Relevant equations

    3. The attempt at a solution
    Because upon reentering, the speeds can get so high that the outside of the spacecraft can get very hot due to kinetic energy converting to heat energy. How does that work? It is hard to imagine? Should I imagine the atoms on the outside of the surface all moving at the speed of the craft so every atom is travelling extremely fast. However, heat is caused by collision of atoms. So collisions must occur. What about the air molecules colliding with the surface of the ship? Would that be the main cause of heating up the ship?
  2. jcsd
  3. Jan 9, 2007 #2


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    Staff Emeritus
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    You are correct thinking that the friction of the air molecules on the crafts surface cause it to heat up. Also the kinetic energy is what is getting converted.
  4. Jan 9, 2007 #3


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    Staff: Mentor

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