Question
A sphere, a cube and a thin circular plate, all of same material and same mass are initially heated to same high temperature.
  1. Plate will cool fastest and cube the slowest.
  2. Sphere will cool fastest and cube the slowest.
  3. Plate will cool fastest and sphere the slowest.
  4. Cube will cool fastest and plate the slowest.

Answer

  1. Plate will cool fastest and sphere the slowest.

Explanation:

loss of heat on cooling is directly proportional to the following factors:

  • Temperature difference between body and surrounding.
  • Surface area exposed to surrounding.
  • Material of object We know that surface area of sphere is minimum and of circular plate is maximum. So sphere cool slowest and circular plate fastest.

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