Dams at two different locations are needed to form a lake.When the lake is filled,the water level will be at the top of both dams.The Dam #2 is twice as high and twice as wide as Dam #1.How much greater is the force of the water on Dam #2 than the force on Dam #1? (Ignore atmospheric pressure;it is pushing on both sides of the dams. )
A)2
B)4
C)8
D)16

Question

Quizplus · Accepted Answer

The force on a dam due to water is proportional to the area of the dam and the square of the height of the water. Since Dam #2 is twice as high and twice as wide as Dam #1, its area is 4 times greater, and the height of the water is twice as high. Therefore, the force on Dam #2 is 4 (area) * 2^2 (height squared) = 16 times greater than the force on Dam #1.

Dams at Two Different Locations Are Needed to Form a Lake.When