MCQ
Two identical balls, $A$ and $B$ , of uniform composition and initially at the same temperature, each absorb exactly the same amount of heat. $A$ is hanging down from the ceiling while $B$ rests on the horizontal floor in the same room. Assuming no subsequent heat loss by the balls, which of the following statements is correct about their final temperatures, $T_A$ and $T_B$ , once the balls have reached their final state?
  • A
    $T_A < T_B$
  • $T_A > T_B$
  • C
    $T_A = T_B$
  • D
    $T_A \leq  T_B$

Answer

Correct option: B.
$T_A > T_B$
b
When the balls are warmed, their centre of masses are moving as radii of balls are increasing. The centre of mass of ball $A$ will come down and that of ball $B$ will go up.In case of ball $A,$ the gravitational potential energy decreases.This corresponds to additional heating of ball.

$T_{A}>T_{B}$

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