If a cross-section area A=0.01 m^2 experiences a pressure difference Δp=2000 Pa, what is the force due to this pressure difference?

• A. 2 N
• B. 200 N
• C. 0.2 N
• D. 20 N

Answer: (D)

When a pressure difference acts across a surface, the net force it produces equals pressure times area: F = Δp × A. Here, Δp = 2000 Pa and A = 0.01 m^2. Since 1 Pa = 1 N/m^2, the force is 2000 N/m^2 × 0.01 m^2 = 20 N. So the force due to this pressure difference is 20 Newtons.

This fits the idea that the same pressure difference over a larger area yields a larger force, and a smaller area yields a smaller force. The other numbers would come from using different areas with the same pressure difference, which isn’t the given case.