A sphere, a cube and a thin circular plate, all made of the same mass and finish are heated to a temperature of $200^{\circ} C$. Which of these objects will cool slowest, when left in air at room temperature?
A
The sphere
B
The cube
C
The circular plate
D
All will cool at same rate
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A
The sphere
a (a)
Objects with more surface area cool faster [Stefan Boltzmann law].
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