The unit for the amount of substance (mass) in the FPS system is the pound.
second
The unit of electric current is amperes (A), not frames per second (fps). Frames per second is a unit used to measure video or screen display speed.
horse power
In the fps system, the unit of acceleration is feet per second squared (ft/s^2).
horse power
FPS (foot-pound-second) is a unit of energy in the imperial system. It is defined as the work done when a force of one pound is applied over a distance of one foot.
It could be pounds per cubic inch, or pounds per cubic foot, or tons per cubic yard. The only substance I know in fps is water which is 62.4 pounds per cubic foot.
In the foot-lb-sec (FPS) system, an appropriate unit would be cubic feet per second (CFS). A more common unit is gallons per minute (GPM). 1 GPM = .00223 CFS.
pound-force per feet2 (lbf/ft2)
The unit of acceleration in the FPS (Foot-Pound-Second) system is feet per second squared (ft/s^2). This unit is used to measure how quickly the velocity of an object is changing over time.
ampere is the unit in all the systems for electric current