A cube, sphere & a thin circular plate (all having same mass and made of same material) are all heated to 300°C and allowed to cool in natural air. Which one will cool the slowest ?
Correct answer: C. Sphere
- A. Cube
- B. Plate
- C. Sphere
- D. All will cool at the same rate
Explanation
For equal mass and material, the sphere has the smallest surface-area-to-volume ratio. It therefore exposes the least area for heat loss per unit mass and cools most slowly.
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