To convert PSI to feet of head, what factor must be multiplied?

To convert PSI (pounds per square inch) to feet of head, the correct factor to use is 2.31. This conversion is based on the relationship between the pressure exerted by a column of water and the height of that column.

Specifically, 1 PSI is equivalent to a column of water that is approximately 2.31 feet high. This relationship arises from the density of water and the gravitational force acting on it. Since pressure is defined as force per unit area, and in the case of water, this force can be characterized by the height of the water column, the height in feet can be calculated from the pressure in PSI using this factor.

Therefore, to find the height of water that a certain PSI corresponds to, one must multiply the PSI value by 2.31. This is a standard conversion used in many engineering and landscaping calculations to determine water pressure-related measurements. The other factors listed do not correspond to the established physics behind the conversion from PSI to feet of water head.