Question

A piston above 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 in KPA

Answer 1

Pressure = force / area

I assume that 350kg is the mass 
Therefore, 

350 x 9.8 (gravity) = 3430N

3430 / 1 = 3430Pa

3.43 KPa

Answer 2

Answer:

3.43 kPa

Explanation:

Pressure is defined as the ratio between the force applied and the area of the surface on which the force is applied:

$p=\frac{F}{A}$

in this problem, the force corresponds to the weight of the load, which is given by the product between its mass (350 kg) and the acceleration due to gravity (9.8 m/s^2):

$F=mg=(350 kg)(9.8 m/s^2)=3430 N$

And since the area on which this force is applied is $A=1 m^2$, the pressure exerted on the upper surface of the liquid is

$p=\frac{F}{A}=\frac{3430 N}{1 m^2}=3430 Pa = 3.43 kPa$