MEDRADSC 1C03 Lecture Notes - Lecture 9: Memory Stick, Resistor, Drift Velocity

• School: McMaster University
• Department: Medical Radiation Sciences
• Course: MEDRADSC 1C03
• Professor: Blaszynski

Document Summary

Medradsc 1c03 lecture 9: current, drift velocity, dc circuits. The flow of electric charges from one place to another. The unit is ampere, which equal to a flow of 1 coulomb per second. (a=c/s) Moving charges as a current: its des(cid:272)(cid:396)i(cid:271)ed as a st(cid:396)ea(cid:373) of (cid:373)o(cid:448)i(cid:374)g (cid:272)ha(cid:396)ges. May range very small currents such as the nerve impulses to a large as the solar wind emitted by the sun: the(cid:396)e (cid:373)ust (cid:271)e a (cid:862)(cid:374)et(cid:863) flo(cid:449) of charges towards one direction. A battery in a circuit gives energy to the electrons and pushes them around a circuit, from the negative terminal of the cell, round the circuit and back to the positive terminal of the cell. How to measure current: the si unit for electric current is ampere (a), (cid:373)alle(cid:396) (cid:272)u(cid:396)(cid:396)e(cid:374)ts a(cid:396)e (cid:373)easu(cid:396)ed i(cid:374) (cid:373)illia(cid:373)pe(cid:396)es (cid:894)(cid:373)a(cid:895). 1ma = 0. 001a: diffe(cid:396)e(cid:374)t ele(cid:272)t(cid:396)i(cid:272)al (cid:272)o(cid:373)po(cid:374)e(cid:374)ts a(cid:374)d applia(cid:374)(cid:272)es (cid:396)e(cid:395)ui(cid:396)e diffe(cid:396)e(cid:374)t sizes of (cid:272)u(cid:396)(cid:396)e(cid:374)t to tu(cid:396)(cid:374) the(cid:373) o(cid:374).