Lecture 2 exercise - piston static pressure (ENGR5003) - Revisica

Lecture 2 exercise - piston static pressureTutorialCurrent specThird5 min

ENGR5003 Lecture 2 student exercise 1 (slide 12)

A gas is contained in a vertical cylinder by a moveable, frictionless piston. The piston has a mass of 4 kg and a cross-sectional area of $35\ \mathrm{cm^2}$ . A compressed spring above the piston exerts a force of 60 N on the piston. If atmospheric pressure is 95 kPa, determine the pressure inside the cylinder.

Formulas you may need

Pressure as force per unit area: $p = F/A$ (learn this)
Static force balance on the piston: $pA = p_{atm}A + mg + F_{spring}$ (learn this: draw the free-body diagram)

p =kPa

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