A block of wood has specific gravity 0.79.When placed in water,what percent of the volume of the wood is above the surface?
A) 0,the block sinks.
B) 21%
C) 79%
D) 50%
E) 100%

Question

A block of wood has specific gravity 0.79.When placed in water,what percent of the volume of the wood is above the surface?
A) 0,the block sinks.
B) 21%
C) 79%
D) 50%
E) ​100%

Quizplus · Accepted Answer

Specific gravity is the ratio of the density of a substance to the density of water. Since the specific gravity of the wood is less than 1, the wood will float in water. The percent of the volume of the wood above the surface of the water is equal to the buoyant force divided by the weight of the wood, which is equal to the specific gravity of the wood. Thus, the percent of the volume of the wood above the surface is 79%. Therefore, the answer is B.

A Block of Wood Has Specific Gravity 0