Segment V2.4: Pop Bottle

(Related to Textbook Section 2.10 - Hydrostatic Force on a Curved Surface)

The hydrostatic force distribution on a curved surface can be quite complex because the force acts normal to the surface, and the direction of the normal varies from point-topoint along the surface. A pressure vessel must be designed to withstand the pressures generated.

If the weight of the pop is neglected, the net force on the complex-shaped bottom of a pop bottle is equal to the pressure times the projected area, a circle the diameter equal to that of the bottle. Thus, when the pressure is 40 psi, a force of approximately 580 lb is needed to fasten the bottom of a 4.3 in. diameter pop bottle to its cylindrical sides.