I need to extract the speed value of a physical object, but the lower the FPS, the more this value is obtained. For example, if at 60 fps the value reaches only 50, then at 10-20 fps this can be considered as 250! How can this be fixed? o_0

(I tried using the framerate expression, but that doesn't help much... Simple example: "speed - framerate", so I decided to ask a question here.)