What term describes the amount of force exerted per unit area on a surface?

What term describes the amount of force exerted per unit area on a surface?

• A. Density
• B. Pressure
• C. Velocity
• D. Temperature

Answer: (B)

Pressure is the amount of force applied per unit area on a surface. It comes from the relationship P = F / A, where increasing the same force over a smaller area raises the pressure, and increasing the area lowers the pressure. The unit are pascals (Pa), equal to one newton per square meter. This concept is central in hydraulics because the fluid pressure transmitted to a piston determines the force the cylinder can produce, since F = P × A.

Density measures how much mass is packed into a volume, not how force is distributed. Velocity is the speed and direction of motion. Temperature is a measure of the average kinetic energy of particles.