Question

A solid cube and a solid sphere of identical material and equal masses are heated to the same temperature and left to cool in the same surroundings. Then:

• A. The cube will cool faster because of its sharp edges.
• B. The cube will cool faster because it has a larger surface area.
• C. The sphere will cool faster because it is smooth.
• D. The sphere will cool faster because it has a larger surface area.

Answer 1

The correct option is B The cube will cool faster because it has a larger surface area.

For the same mass the a sphere has the least volume and surface area. Radiation is directly affected by surface area. Since the cube will have larger surface area, it will cool faster.