Question

A piston above a liquid in a closed container has an area of 1m2. The piston carries a load of 350 kg. What will be the external pressure on the upper surface of the liquid?
A. 27.3 kPa
B. 3.43 kPa
C. 4.90 kPa
D. 68.6 kPa

Answer 1

Answer;

B. 3.43 kPa

Explanation;

Pressure is given by the formula;

Pressure = Force / Area

Force is the product of mass and acceleration due to gravity. 

 Thus;  Force = mass x acceleration due to gravity

Substituting;

               Force = (350 kg) x (9.8 m/s²)

               Force = 3430 N

Then, using the first equation;

                Pressure = 3430 N / 1m² or Pa

                            = 3.43 kPa