A block of ice 30.5 cm thick floating in fresh water just supports a man weighing 801 N. If the specific gravity of ice is 0.917, the smallest area the block can have is A) 3.22 m². B) 3.57 m². C) 2.88 m². D) 1.45 m². E) 0.269 m².

Question

Quizplus · Accepted Answer

The smallest area the block can have is 3.22 m². This is because the buoyant force on the block must be equal to the weight of the man, and the buoyant force is equal to the weight of the water displaced by the block. The weight of the water displaced is equal to the volume of the water displaced multiplied by the density of the water. The volume of the water displaced is equal to the area of the block multiplied by the thickness of the block. Therefore, the area of the block must be equal to the weight of the man divided by the density of the water multiplied by the thickness of the block.

A Block of Ice 30