pa piece of paper horizontal, you should blow over. not undert When we try to close a water tap with our fingers, fast jets of water through the openings between our fingers The size of the needle of a syringe controls flow rate better than the thumbs p ure exerted by a doctor while administering an injection Abud Blowing out of a small hole in a vessel results in a backward thrust on the vessel

When we try to close a water tap with our fingers, fast jets of water gush through the openings between our fingers.

When we try to close a water tap with our fingers , fast jets of water gush through the oopenings between our fingerss

Explain why (a). To keep a piece of paper horizontal, you should blow over, not under, it (b). When w try to close a water tap with our fingers, fast jets of water gush through the openings between our fingers (c). The size of the needle of a syringe controls flow rate better than the thumb pressure exerted by a doctor while administering an injection (d). A fluid flowing out of a small hole in a vessel results in a backward thrust on the vessel (e). A spinning cricket ball in air does not follow a parabolic trajectory.

Explain why When we try to close a water tap with our fingers, fast jets of water gush through the openings between our fingers

Explain why When we try to close a watertap with our fingers, fast jets of water gush through the openings between our fingers

Explain why When we try to close a water tap with our fingers. Fast jets of water gush through the openings between our fingers

When an object moves through a fluid, as when a ball falls through air or a glass sphere falls through water te fluid exerts a viscous foce F on the object this force tends to slow the object for a small sphere of radius r moving is given by stoke's law, F_(w)=6pietarv . in this formula eta in the coefficient of viscosity of the fluid which is the proportionality constant that determines how much tangential force is required to move a fluid layer at a constant speed v, when the layer has an area A and is located a perpendicular distance z from and immobile surface. the magnitude of the force is given by F=etaAv//z . For a viscous fluid to move from location 2 to location 1 along 2 must exceed that at location 1, poiseuilles's law given the volumes flow rate Q that results from such a pressure difference P_(2)-P_(1) . The flow rate of expressed by the formula Q=(piR^(4)(P_(2)-P_(1)))/(8etaL) poiseuille's law remains valid as long as the fluid flow is laminar. For a sfficiently high speed however the flow becomes turbulent flow is laminar as long as the reynolds number is less than approximately 2000. This number is given by the formula R_(e)=(2overline(v)rhoR)/(eta) In which overline(v) is the average speed rho is the density eta is the coefficient of viscosity of the fluid and R is the radius of the pipe. Take the density of water to be rho=1000kg//m^(3) Q. Blood vessel is 0.10 m in length and has a radius of 1.5xx10^(-2) m blood flows at rate of 10^(-7)m^(3)//s through this vessel. The pressure difference that must be maintained in this flow between the two ends of the vessel is 20 Pa what is the viscosity sufficient of blood?