Physics-
General
Easy
Question
Two spheres of different materials one with double the radius and one-fourth wall thickness of the other are filled with ice. If the time taken for complete melting of ice in the larger sphere is 25 minute and for smaller one is 16 minute, the ratio of thermal conductivities of the materials of larger spheres to that of smaller sphere is
- 4:5
- 5:4
- 25:8
- 8:25
The correct answer is: 8:25
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