If F is 400 N and S=2m^2, find the pressure(P) ?

2. P = F/A

In this case, A = S = area

3. what does S mean,displacement?

4. From the unit given, it's area

5. Originally Posted by jashansinghal
what does S mean,displacement?
S cannot be displacement because it has dimensions of (Length)^2 whereas displacement has dimensions of (Length). This means that S is an area of some kind although it is more usual to use A to denote an area

$P = \frac{F}{A}cos \alpha$ where $\alpha$ is the angle between the force and the vertical and will be measured in $Pa$ or $Nm^{-2}$

In your example it's probably a perpendicular force so $cos \alpha = 1$ and it reduces to $P=\frac{F}{A}$