Electricity -- The Basics!. Interactions of Charge Centers.

Slides:



Advertisements
Similar presentations
Electrostatics, Circuits, and Magnetism 4/29/2008
Advertisements

NEWTONIAN MECHANICS. Kinematic equations Frictional Force.
Circuits Electromotive Force Work, Energy and emf
+ V (Volt) = W (work done, J) Q (charge, C)
Chapter 30. Potential and Field
CAPACITORS SLIDES BY: ZIL E HUMA. OBJECTIVES CHARGING OF THE CAPACITORS DISCHARGING OF THE CAPACITORS DIELECTRIC MATERIALS FACTORS EFFECTING THE VALUES.
TOC 1 Physics 212 and 222 Circuit Elements and Electric Power Resistors Capacitors Inductors.
Fundamentals of Circuits: Direct Current (DC)
DC circuits Physics Department, New York City College of Technology.
Basic Electronics. Need to know Definition of basic electrical paramater A set of rules for elementary circuit analysis The means of current flow in circuits.
Cellular Neuroscience (207) Ian Parker Lecture # 1 - Enough (but not too much!) electronics to call yourself a cellular neurophysiologist
Circuits Resistors, Capacitors and Inductors 1 Resistors Capacitors Inductors.
Cellular Neuroscience (207) Ian Parker Lecture # 1 - Enough (but not too much!) electronics to call yourself a cellular neurophysiologist
Lecture B Electrical circuits, power supplies and passive circuit elements.
Current and Voltage. Current Flow rate of electricity Current flows from + to – Measured in Amps – 1 Amp = 1 Coulomb per second Actually electrons flow.
Electricity Foundations of Physics. Electricity The movement of charge from one place to another Requires energy to move the charge Also requires conductors.
Current, Resistance, and Simple Circuits.  A capacitor is a device used to store electrical energy.  There are two different ways to arrange circuit.
L 26 Electricity and Magnetism [3] Electric circuits Electric circuits what conducts electricity what conducts electricity what doesn’t conduct electricity.
Lecture 13 Direct Current Circuits
AP Physics. Capacitors in Series C3C3 C2C2 C1C1 Capacitors in series share the same charge magnitude.
Electric Circuits Just like we can use pipes to carry water, we can use wires to carry electricity. We can use this concept to understand electric circuits.
Terms Ohm The ohm (symbol: Ω) is the SI unit of **electrical impedance or, in the direct current case, electrical resistance, named after Georg Simon.
Electrical Resistance and Ohm’s Law Electric circuits are used to convert electrical energy into some other form of energy we need.
Chapter 34 Electric Current Voltage is an “electrical pressure that can produce a flow of charge, or current, within a conductor. The flow is restrained.
Electrostatics. Electric Charge and Electric Field.
Electricity Ch. 11. Electric Charge All matter is made of atoms Atoms contain 2 charged particles—what are they? These charges produce attractive and.
AP Physics B Summer Course 年 AP 物理 B 暑假班 M Sittig Session 10 Reminders.
Current of Electricity Electric Current Potential Difference Resistance and Resistivity Electromotive Force.
Capacitors, Batteries. Capacitors Create a difference in Potential based upon how much charge is stored V = q/C (V) C : Capacitance C = k ε o A /d k :
describes the relationship between current, voltage, and resistance greater the voltage across a device with resistance, the greater the current through.
How does the new Science 9 Electricity Unit compare to the current Science 10 curriculum?
ELECTRIC CIRCUITS BASICS. Electricity Basics Electricity starts with electrons. Every atom contains one or more electrons. Electrons have a negative charge.
Electric field, Electric Potential Difference and Capacitance.
Electrostatics #5 Capacitance. Capacitance I. Define capacitance and a capacitor: Capacitance is defined as the ability of an object to store charge.
Determine the mathematical models that capture the behavior of an electrical system 1.Elements making up an electrical system 2.First-principles modeling.
ELECTRIC CURRENTS. SIMPLE CIRCUIT What’s providing the energy? What’s “moving” in the circuit? What’s causing the movement? e.m.f. = Electromotive Force.
Electric Currents & Circuits AP – Ch 20 & 21. Intro Stuff Circuit? – Power Supply – Resistance.
Electrical Energy. Electric Potential Energy Note: Energy is scalar, so keep the sign on the charge +d means movement in the same direction as the E-field.
Electricity and Electronics Base of Modern Technology.
5.2.2 D.C. Circuits Practical circuits Electromotive force and internal resistance Kirchhoff’s laws Series and parallel arrangements Potential divider.
1 Mid-term review Charges and current. Coulomb’s Law. Electric field, flux, potential and Gauss’s Law. Passive circuit components.  Resistance and resistor,
Electricity. Flow of electric charges (electrons) How much? Current ( I ) I = Δq/ Δt (A) VC.
Methods of Charging Conduction – A Charged Object comes in CONtact with a neutral object. – The neutral object takes on the same Net Charge as the Charged.
Electricity and Circuit. Types of Electricity Static Electricity – no motion of free charges Current Electricity – motion of free charges – Direct Current.
Current Resistance Electric Power & Energy. Voltage (V) Electric potential difference between 2 points on a conductor Sometimes described as “electric.
Definitions. Electricity Electric Current Current Direction The current direction is from positive to negative but the electron direction is from negative.
Electric Current Everything (water, heat, smells, …) flows from areas of high concentration to areas of lower concentration. Electricity is no different.
1 Mid-term review Charges and current. Coulomb’s Law. Electric field, flux, potential and Gauss’s Law. Passive circuit components.  Resistance and resistor,
Chapter 9 CAPACITOR.
Objectives: 1. Define and calculate the capacitance of a capacitor. 2. Describe the factors affecting the capacitance of the capacitor. 3. Calculate the.
Objectives: 1. Define and calculate the capacitance of a capacitor. 2. Describe the factors affecting the capacitance of the capacitor. 3. Calculate the.
Chapter 19 DC Circuits. EMF and Terminal Voltage Any device that can transform a type of energy into electric energy is called a source of electromotive.
Current and Resistance El Paso Independent School District.
Electric Current Chapter 34.2, 34.4, 34.5, and Notes.
Electrical circuits, power supplies and passive circuit elements
Chapter 11 Capacitance.
Capacitance Capacitance occurs whenever electrical conductors are separated by a dielectric, or insulating material. Applying a voltage to the conductors.
Chapter 27. Current and Resistance
Electrical circuits, power supplies and passive circuit elements
Capacitors, Batteries.
Electric Circuits.
Lecture 15 Review: Capacitors Related educational materials:
ELECTROMOTIVE FORCE AND POTENTIAL DIFFERENCE
Electric Current Chapter 17.
Chapter 27. Current and Resistance
Chapter 27. Current and Resistance
Electricity Review CH
Chapter 27. Current and Resistance
Ohm’s Law & Circuits Chapter 7.2 & 7.3.
Electric Current Chapter 34.
Presentation transcript:

Electricity -- The Basics!

Interactions of Charge Centers

Basic Electrical Relationships Coulomb -- a unit of charge 1 coulomb = 6.2×10 18 elementary charges Coulomb’s Law The electrical analog of velocity is current: The electrical analog of force is electromotive force (E): (force in N)

Electrical Potential Potential to do work is always measured relative to some reference state. In electricity, zero potential (ground) can be viewed as an electrically neutral location that is an infinite sink for charge (next slide).

Movement of Charges A good analogy is the expansion of gases into larger containers -- although the proximate cause of the expansion is quite different!

Resistance Resistance is that which limits current flow (for a given potential) and consumes electrical energy (resistances convert electrical energy to other forms such as heat). R (resistance) is measured in ohms (  ; G (conductance, its inverse) is measured in siemens (S).

A Purely Resistive Circuit Which way does the current flow?

Fluid Analog to Resistance, Current and Potential "ResistanceHydraulicAnalogy" by Sbyrnes321 - Own work. Licensed under CC0 via Commons - vg#/media/File:ResistanceHydraulicAnalogy.svg Pressure difference is potential difference Flow is like current

Series and Parallel Resistive Circuits Can you draw an analogy to these circuits using water flow?

Capacitance Capacitance is the ability to store electrical charge; the larger the capacitance, the greater that ability. Capacitors (ideal ones) do not consume energy – whatever energy they store can be retrieved.

Capacitance Energy storage -- the electrical analog of elasticity

A Purely Capacitive Circuit

Equilibrium in a capacitive circuit

RC Circuits RC (resistive-capacitive) circuits both store and consume energy. These will be important in our discussions of membrane potentials, especially ones that vary and move.

An RC Circuit

The Time Constant  A measure of the time needed to charge an RC circuit.  = RC If t =  then 1-(1/e) = 1-(1/2.7) = 1 – 0.37 = 0.63

The Effect of the Time Constant