A cylindrical copper conductor AB length L areaaof cross-section a has large number of free electrons which at mean temperature move at random within the body of the conductorlike the molecules of a gas. The averagethermal motion at room temperature is of the enter of 10^(5)ms^(-1) where a potential difference V is applied free electronic in the condictior experience , the free electrons in the conductorexperience force and are accelerated towards the positive emf of the condutor on their gained kinetic energy After each collision the free electronic are angle acceleration due of the electric field , towards the positive end the conductor andnext collision with the ions/atoms of the electrons The average speed of the free electrons with which they drift toward the positive and of the conductor under theeffect of applied electric field is called drift of the electrons The speed of electrons in a conductor is small (= 10^(-4) ms^(-1)) when the switch is closed, the bulb at a distance glows immediately. It is so because