Thermal Physics> Thought provoking question...

A solid sphere,a cube and a circular plate all made of the same material and having the same mass are heated to 300 centigrade and are allowed to cool under the same circumstances.Which of them will cool the fastest and slowest?Please explain.

Jayakant ------ ------ , 16 Years ago

Grade 11

4 Answers

Badiuddin askIITians.ismu Expert

Dear Jayakany

Here is the concept of exposed area to the atmosphere.

we know that for same volume sphere has minimum surface area,plate has maximum surface area.

so sphere cool slowest and plate coo fastest

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Last Activity: 16 Years ago

rishi raj mishra

since we know that sphere has minimum surface area and plate has maximum surface area for same volume.and as per newtons law of cooling heat loss is directly propotional to exposed area.so here Cube will be cooled faster than sphere but slower than circular plate means 1.circular plate 2. cube 3. sphere

Last Activity: 8 Years ago

Rebanta Raha

We know, the speed of cooling down is directly proportional to the exposed area. In this case, plate has greatest exposed area and the sphere has the lowest exposed area. And the cube is in the middle of these 2 . So, first, the plate will cool down, then the cube, and lastly, the sphere will cool down.

Last Activity: 8 Years ago