find the weight of the liquid in a cubical container 3 cm on a side

Question

The weight of a liquid varies directly as its volume V. If the weight of the liquid in a cubical container 5 cm on a side is 250 g,find the weight of the liquid in a cubical container 3 cm on a side.

Answer 1

Assuming that by "weight," you mean "mass" (because weight = mass * the acceleration due to gravity), the following is true

 

1. density = mass/volume

2. the volume of Container A = (3 cm)³ = 27 cm³ 

3. the volume of Container B = (5 cm)³ = 125 cm³

4. the liquid has the same density in both containers.

5. therefore, m/27 cm³ = 250 g/125 cm³

6. solve for m (mass)

7. m = (250 g * 27 cm^3)/125 cm³

8. m = 54 g

 

To find the weight, convert to kg: 54 g * 1 kg/1000 g = .054 kg. Then, m*g (acceleration due to gravity) = .054 kg * 9.81 m/s² = .52974 kg*m/s² = .52974 N