Physics · Heat transfer: conduction, convection and radiation
A sphere, a cube and a thin circular disc all made of the same material, have sa
A sphere, a cube and a thin circular disc all made of the same material, have same mass. Their initial temperature is \( 3 \times 10^{3}^{\circ} \mathrm{C} . \) The body which cools rapidly is :
- A. sphere
- B. cube
- C. both sphere and cube
- D. circular plate
Step-by-step solution
The cooling rate by radiation and convection is proportional to the surface area. For a given mass and material, the volume is constant. Among a sphere, cube, and thin circular disc of equal volume, the thin disc has the largest surface area, allowing it to lose heat fastest and cool most rapidly.
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