Fuuu w turther your understanding of mechanical stress. part aone kind of stress is called pressure. pressure is calculated as force divided by area. force is a push or a pull. its measured in units such as pounds or newtons. area is measured in units such as square inches or squareneters. the equation for calculating pressure is p= where p is pressure, f is force, and a is area. jse the equation to calculate the average pressure on the membrane below. express your answer in units ofjounds per square inch (psi).f = 60 lb. a = 24 sq. in.