Resistance. What is resistance? Resistance is the amount that a material holds back the flow of electrons Atomic nuclei (plural of nucleus) get in the.

Slides:

Advertisements

Similar presentations

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

Advertisements

April 26 Physics. Homework #4 In: Label each diagram as series or parallel:

Ohm’s Law, Energy, Power, Series and Parallel Circuits Circuits 1 Fall 2005 Harding University Jonathan White.

What Affects the Flow of Electricity? Some materials are good conductors. Electricity flows best through conductors. The base and the wires of a light.

Resistance. Definition Opposition to the flow of electrons When electrons pass through materials with high resistance, they collide with its molecules.

Cells have positive and negative electrodes.

RESISTANCE AND OHM’S LAW. A closer look at insulators and conductors Conductors: electrons loosely bound to nuclei –Electrons flow easily when voltage.

The amount of charge passing a point in a given time interval is.

S Describe qualitatively the relationship among current, voltage and resistance. KEY WORDS Ohm’s Law.

Ohm’s Law The most important fundamental law in electronics is Ohm’s law, which relates voltage, current, and resistance. Georg Simon Ohm ( ) studied.

Electrical Resistance Gr 9 Science. 4 Electrical resistance = the property of a substance that hinders electric current and converts electrical energy.

Circuits & Electronics

Making Sense of Circuits.  How much an object resists electricity flowing  Increasing resistance, lowers the current  Measured in Ohms (Ω)

Electrical Resistance and Ohm’s Law Electric circuits are used to convert electrical energy into some other form of energy we need.

 Georg Simon Ohm   German  Physicist  HIGH SCHOOL TEACHER!!!!

Electrical resistance Resistance measures how difficult it is for current to flow.

Ohm’s Law & Electrical Power. Resistance - the tendency for a material to oppose the flow of electronsResistance - the tendency for a material to oppose.

Warmup: Concept: OHM’s Law. Electrical current is a measure of the rate at which electrical charge moves in a circuit. Electrical current is measured.

Electrical Potential (Voltage) Answers (Page 303)

Electricity (resistance, current, voltage) Instructor: Shelia Chase.

CURRENT ELECTRICITY Characteristics of Current Electricity.

4.2.3B Electrical Power What About Watts?. Power Law Moving electrons (current) requires ENERGY How much energy gets used depends on: Strength of push.

 a measure of how difficult it is for electric current to travel through a material  good conductors (metals) have low resistance, while insulators.

Ohm’s Law Conductor A conductor is a material that current can pass through easily, like metals.

Electrical Resistance Electrical resistance is a measure of how difficult it is for electricity (electrons) to flow through a material. The units of resistance.

 Measuring current may be accomplished by using a meter called an Ammeter  This meter is placed in the path of the electron flow, and reads the flow.

Electric Current, Resistance and Ohm’s Law

Unit 3, Chapter 8 Integrated Science. Unit Three: Electricity and Magnetism 8.1 Ohm's Law 8.2 Work, Energy, and Power Chapter 8 Electrical Relationships.

Ch Electricity II. Electric Current  Cell and Battery  Potential Difference  Current  Resistance  Ohm’s Law.

T By iTutor.comiTutor.com.

Ch Electricity II. Electric Current  Cell and Battery  Potential Difference  Current  Resistance  Ohm’s Law.

Circuits. Diagramming Circuits 1. conductor 2. light bulb 3. switch 4. battery 5. resistor 6. ammeter 7. voltmeter.

WALT: about resistance and Ohm‘s law Success Criteria: You should know and understand the relationship between voltage, current and resistance.

 When electric charges flow they experience opposition or resistance which reduces the amount of energy they have  Greater resistance -> greater amount.

Electric Current Current, Ohms Law & Power. Electric Current  Electric current is related to the voltage that produces it, and the resistance that opposes.

8.3 Resistance and Ohm’s Law.  Resistance is the property of any material that slows down the flow of electrons and converts electrical energy into other.

Electric Current Chapter 34.2, 34.4, 34.5, and Notes.

Measuring Electricity. Electric Potential – the electrical energy that an electron possesses. Electric current is a measure of the rate at which the electric.

Electric Current Electric current – The net movement of electric charges in a single direction through a wire or conductor. Voltage difference – The force.

Resistance Resistance Loads Conductors Superconductors Ohm’s Law

Science 9 Ohm’s Law.

ELECTRICAL RESISTANCE

Ohm’s Law & Electrical Power

RESISTANCE AND OHM’S LAW

Check your Understanding

Resistance and Ohm’s Law

Electric circuits e the significance of and the relationship between current, voltage and resistance.

Ch Electricity II. Electric Current (p ) Circuit

Foundations of Physical Science

Ch Electricity II. Electric Current Circuit Potential Difference

Resistance in Circuits

Electrical Potential Joules units: = Volt = V Coulomb

Electric Current.

Resistance How much energy does it take to push a coulomb of charge across a filament? Defined as the ratio of POTENTIAL DIFFERENCE across the LOAD POTENTIAL.

Ch Electricity II. Electric Current (p ) Circuit

Current and Resistance

Resistance in Circuits

Electricity II. Electric Current Circuit Potential Difference Current

Please bring your book tomorrow.

Voltage Difference The difference in electrical potential between two places. Unit of measure = V (volts) Voltage causes current to flow through an electric.

Dynamic Electricity.

Electric Resistance describes how an electrical conductor (wire) opposes the flow of a current (flow of electrons) to overcome this opposition a voltage.

Chapters 18 & 19 What is the definition of electric potential?

Example Example 1: An electric lamp is rated 110 W, 200 V. When the lamp is operated at its rated power and voltage, calculate a) the current flowing through.

Presentation transcript:

Resistance

What is resistance? Resistance is the amount that a material holds back the flow of electrons Atomic nuclei (plural of nucleus) get in the way of moving electrons Similar to the idea of friction

What is resistance? Resistance causes electrons to use some of their energy to move through the wire – there is a potential difference

What is resistance? Measured in units called Ohms (Ώ) – named after German physicist Georg Ohm (1789 – 1854)

Ohm’s Law Ohm noticed the relationship between voltage and current in electrical circuits (Ohm’s Law) V = I x R

What a waste! Energy lost to a resistor is converted to heat and/or light We can use the resistance of materials to our advantage

What a waste! For example, light bulb filaments are made out of Tungsten

What a waste! The longer an extension cord or speaker wire is, the more resistance it has Reduced sound/light efficiency

Food for thought What happens to current and voltage in an electrical circuit if we increase resistance?