I'm a little confused about the conversion between lbm and lbf (mass pounds and force pounds). I'm doing a problem where I'm using newton's 2nd law to calculate mass flow rate. F= Δ((Mass flow rate)*Velocity) I know my force is 400 lbf and velocity is 40 ft/s so mass flow rate is 10 lbf/(ft/s) Is the the same as 10 lbm/s? Or do I need to divide by g or something? Thanks!