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Homework Help: Thermal expansion in heat engine

  1. Nov 11, 2008 #1
    A brass piston of diameter 25 cm at 20 degrees C must be able to function at 150 degrees C.
    In order to do so it must fit inside a steel cylidrical chamber. What must the minimum initial diameter of the cylinder be so that the piston never rubs against it.
    alpha=2x10^-5 for brass
    alpha=1.2x10^-5 for steel
    dT=130 degrees C

    dL=alpha*L0*dT
    dV=beta*V0*dT

    I don't know whether this is Volume or linear thermal expansion. I think it is volume but there is no given value for length of the piston or cylinder so initial volume and delta V are unknown.
     
  2. jcsd
  3. Nov 12, 2008 #2

    Redbelly98

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    Hint: diameter is a linear dimension quantity.

    p.s. welcome to PF.
     
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