What forces fluid from the blood into the Bowman's capsule?

Fluid is forced from the blood into Bowman's capsule primarily due to the hydrostatic pressure generated by the blood flow within the glomeruli. This pressure exceeds the osmotic pressure of the plasma proteins and the hydrostatic pressure within the capsule itself, leading to filtration. The process is part of renal filtration, where substances are selectively filtered from the bloodstream to form urine.