Question

In a science demonstration, 4 to 6 plastic garbage bags are arranged under a 2 m by 2 m piece of plywood. A volunteer stands on the plywood and others blow into the bags to "levitate" the volunteer. If four bags are used and a 140 lb person is on the plywood, what is the pressure that must be supplied by each of the four blowers (in Pa)? What if 6 bags and blowers were used? (Assume the plywood has no mass).

Pressure = 140/4m^2. The number of bags has no influence, in any case, the pressure above is needed to move the plank.

Answer 1

39 Pa for each of 4 blowers; 26 Pa for each of 6