View Vow How many electrons go past a point every second in a wire if the current is 12 Amps?

Slides:



Advertisements
Similar presentations
Ch Electricity II. Electric Current (p ) Circuit Potential Difference Current Resistance Ohms Law.
Advertisements

CH 20-1.
What do you already know about it?
Ohm’s Law Physics 102 Professor Lee Carkner Lecture 14.
Resistivity Definition Whiteboards. What determines the resistance of a piece of wire?
 Rate (how fast) at which charges pass a given point  Measured in Amperes or amps  Current (I)  Electrons moving in a wire make up current and provide.
Aim: How can we explain electric current and resistance? Do Now: Two charged plates are connected by a wire conductor. What will happen? + -
Bellwork If it takes 8 Joules of work to move a charge of 2 coulombs around a circuit, then what is the potential difference in the circuit?
Electricity and Magnetism Unit III. I Electrostatics 0 The study of electric charges at rest and their electric fields and potentials 0 Charges at rest.
2/25 Do now Sphere A has a positive charge of 9 C. Sphere B and sphere C are neutral. Sphere A is used to charge sphere B by conduction. Sphere A is used.
Circuits Electric Circuit: a closed path along which charged particles move Electric Current: the rate at which a charge passes a given point in a circuit.
Electrical Energy - Moving electrons in a path is electricity
Do Now What work is required to move 7 coulombs of charge through a potential difference of 3 volts?
Electrical Resistance Electrons like any other moving body follow the path of least resistance. Truemper 10/24/2011.
Resistivity and Current ELECTRIC CURRENT An electric CURRENT exists whenever electric charge flows through a region, e.g., a simple light bulb circuit.
Electrical Resistance Activity. Curriculum Big Idea: Energy can be transferred between objects and/or can be converted into different forms. Concept:
Ch  The opposition to the motion of charge in a conductor.  For most metals, resistance is constant over a wide range of applied potential differences.
Resistivity Electricity Lesson 5. Learning Objectives To define resistivity. To know what causes resistance. To know how to measure resistance.
Electric Circuits. What is Electric Current? Current in a river –The movement of water molecules Higher current = more water passing a given point each.
EXAMPLE 27.1: A copper wire carries a current of 10 A. It has a cross- sectional area of 0.05 cm 2. Estimate the drift velocity of the electrons.
Electric Current Flow of electric charges through a piece of material Amount of flow depends on material and the potential difference across the material.
Making your own Resistor. Shade an area on grid paper 1cm x 20cm Make sure that you shade this area really, really well! It must be really shiny otherwise.
Electric Current. The rate of flow of electric charges Unit of measure is coulombs per second, or amperes I – rate of flow (current) (amps) q – charge.
Ch Electricity II. Electric Current  Cell and Battery  Potential Difference  Current  Resistance  Ohm’s Law.
Principles of Physics. So far, we’ve talked about non-moving charge We know that charged objects :  exert an electrostatic force on each other  move.
Chapter 27: Current and Resistance
Electrical Resistance
Electric Current.  Electric current is the continuous flow of electric charges through a material.  Needed to power any electrical device.  Measured.
Jag Mark What kind of charging does the PowerMat utilize?
Ch Electricity II. Electric Current  Cell and Battery  Potential Difference  Current  Resistance  Ohm’s Law.
 The opposition of a material to the flow of charge through it.  Measured in ohms (  ).
Mar 30 Today’s Activities -AP Test Must Memorize and Gravitational Potential Energy -Electricity Background Knowledge -AP Practice Questions set #6 Tomorrow’s.
What do you think? What do you think these four pictures have in common?
Regents Physics 11/10/2008 Mrs. Nephew. Electric Current The rate at which charge passes a given point in a circuit. Electric Circuit=a closed path along.
Electrical Resistance
Cell energy ☺ electron lamp.
CH 5 – Electricity and Magnetism
Aim: How does resistivity affect resistance?
Aim: How can we account for resistivity and capacitance?
Electric Current Electric current I is the rate of the flow of charge Q through a cross-section A in a unit of time t. A + - Wire +Q t One ampere A is.
Voltage, Current, and Resistance
RESISTANCE.
A fixed resistor A filament lamp An LED Sketch an I/V graph for:
Electricity - Current.
Electrical Theory turn to chapter 8 in the A & P mechanics general handbook.
☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺ ☺.
Ch Electricity II. Electric Current (p ) Circuit
Measurements in Electric Circuits
Resistance in Circuits
Conductance / Resistance / Factors
Current and Resistance
Voltage, Current and Resistance
Announcements Electrostatics – Potential worksheet is due tomorrow [All materials are posted online under the electromagnetism post] Electrostatics Quiz.
Electrical Stopping Power Electrical Resistance
Voltage, Current and Resistance
RESISTANCE The opposition to the flow of electric current
Chapter 9: Current and resistance
Electric Current and Electrical Energy
Electric Current.
RESISTANCE.
Ch Electricity II. Electric Current (p ) Circuit
Chapter 19-2: Pages Physics
Electrical Stopping Power Introduction to Resistance
Electricity Chapter 19.
Do Now (Homework due tomorrow) How much electrical energy s consumed by a fan that is rated for 9V and 2A and is left on for 1 year? Common assessment.
Electricity II. Electric Current Circuit Potential Difference Current
Voltage Difference The difference in electrical potential between two places. Unit of measure = V (volts) Voltage causes current to flow through an electric.
Electricity Electric Current.
Aim: How do we explain resistance?
T- Norah Ali Al- moneef king Saud university
Presentation transcript:

View Vow How many electrons go past a point every second in a wire if the current is 12 Amps?

Objectives Understand that current tells us how much charge (think moving electrons! – but more to come on this) moves past a certain point every second. We all know “Resistance is futile”…but what is resistance when we are talking about Current?

Homework Castle Learning – Current and Resistance

Test Corrections today post and tomorrow. I do have a meeting today but I will be in here so feel free to come today for corrections. Please look over, ask questions, check the scoring and then return to your mailbox.

Worksheet Current

4.2.2 Electrical Resistance Electrical Stopping Power

Definitions resistance: OPPOSITION TO CURRENT unit: Ω factors that change resistance: resistivity: MATERIAL length cross-sectional area temperature

R A Resistance Factors R ρ R L R Temp. NEXT

R A Resistance Factors R ρ R L R Temp. To build an “ideal” conductor with the smallest possible resistance you would select one that is: LOW RESISTIVITY, SHORT, WIDE, COLD

Determine the resistance of a 1.0 meter long copper wire with a cross-sectional area of 0.01 meter 2. Example #1 R = ρL / A R = (1.72 x Ω·m)(1.0 m) / (0.01 m 2 ) R = 1.72 x Ω

A piece of wire that has a length of 5.0 x 10 7 meters and a cross-sectional area of meter 2 has a resistance of 31.8 ohms. –What is the composition of this wire? Example #2 R = ρL / A ρ = RA / L ρ = (31.8 Ω)(0.025 m 2 ) / (5.0 x 10 7 m) ρ = 1.59 x Ω·m

End of PRACTICE