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Homework Help: Thermal Expansion of Spheres

  1. Oct 24, 2011 #1
    Explain why the thermal expansion of a spherical shell made of a homogeneous solid is equivalent to that of solid sphere of the same material.

    I guess these equations would be of some help.
    α→ Coefficient of linear expansion.
    A→ Area
    T→ Temperature

    α→ Coefficient of linear expansion.
    V→ Volume
    T→ Temperature

    I'm not sure if i understood the question right.
    By "equivalent thermal expansion" i guess they mean to say the radius increases by same amount during the expansion.
    So i set out relating the two radii.
    Took two spheres, one hollow, the other solid, of same dimensions, i.e., same radii.

    For the Shell,


    For the solid sphere, similarly, relating the volume,

    But, failed to prove them to be the same.
    So what exactly do they intend to ask? And how do i hit it?...
  2. jcsd
  3. Oct 25, 2011 #2
    Does this work?

    Attached Files:

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