Question

A patient receiving blood transfusion with a bottle containing blood which is elevated 75.0cm above the arm of the patient. If force of 50N moves the blood to the middle which is 4.0 cm long find a diameter of the needle

Answer 1

$$F=\rho gh A\\50=0.25\pi (9.8)(1000)(0.75)d^2\\d=0.093\ m$$