text: pascals principle/ hydrualics? i have a bunch of physical science homework that i didnt do last semester so i have to do it now and i dont know any of the math portions so i could really use some help:  a hyraulic lift chair has its seat attached to a piston with an area of 11.2cm(2) yada yada yada the other piston exerts with an area of 4.12 cm(2) person on chair exerts downward force of 219 n what force needs to be exerted on the small piston to ;ift the seat.  7468 list on large piston, wit an area of 28.27cm(2), how much force must be exerted on small piston if it has an area of 1.325cm(2)? 1.) the force over the area of the large piston will be equal to the force over the area of the small piston. (f1/a1 = f2/a2)  so: f1 = 219n a1 = 11.2 cm^2 f2 = x a2 = 4.12 cm^2  219 / 11.2 = x / 4.12 x = 19.5536 * 4.12 x = 80.56 n  armed with that, you should be able to do #2.