ENERGY Define voltage operationally Explain what gives rise

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ENERGY

ENERGY

 • Define voltage operationally • Explain what gives rise to current in the

• Define voltage operationally • Explain what gives rise to current in the circuit • Differentiate current from voltage operationally • State Ohm’s law

5 Now let’s find out, what 3 this topic is all about! READY? 1

5 Now let’s find out, what 3 this topic is all about! READY? 1 2 4

Energy In physics, energy is a scalar physical quantity that describes the amount of

Energy In physics, energy is a scalar physical quantity that describes the amount of work that can be performed by a force, an attribute of objects and systems that is subject to a conservation law.

Different forms of energy include kinetic, potential, thermal, gravitational, sound, light, elastic, and electromagnetic

Different forms of energy include kinetic, potential, thermal, gravitational, sound, light, elastic, and electromagnetic energy. The forms of energy are often named after a related force.

Electricity is almost an indispensable part of our lives. Our lighting, heating, transport and

Electricity is almost an indispensable part of our lives. Our lighting, heating, transport and communication are all dependent on it.

ELECTRIC CIRCUIT

ELECTRIC CIRCUIT

Simple Electric Circuit Electric current Voltage Conductors and Insulators Ohm’s Law

Simple Electric Circuit Electric current Voltage Conductors and Insulators Ohm’s Law

Is any arrangement of materials that provides a path for electrons to flow. It

Is any arrangement of materials that provides a path for electrons to flow. It consist of a source of electrical energy, connecting wires, and a load. The load may be a bulb, a radio, an electric stove, or any other appliances.

Electrical Symbol

Electrical Symbol

 • An electric circuit can be opened or closed by turning a switch

• An electric circuit can be opened or closed by turning a switch on or off. • At the source , electrical energy is converted from other forms, usually chemical, mechanical, and thermal energy. In the load, electrical energy is likewise converted into other forms like light, motion, sound, and thermal energy.

Bulb Switch Wire Dry Cell A simple circuit/circuit A simple circuit/ diagram circuit diagram

Bulb Switch Wire Dry Cell A simple circuit/circuit A simple circuit/ diagram circuit diagram

Electric current • In electric circuits, the energy carriers are free electrons or electrons

Electric current • In electric circuits, the energy carriers are free electrons or electrons loosely bound to the atomic nuclei. An electron has a charge of 1. 6 x 10^18 coulomb. The coulomb (C) is the basic unit of electric charge. To produce 1 coulomb of electric charge, 6. 3 x 10^18 electron is required.

 • Electric current is measured by determining the number of charges q passing

• Electric current is measured by determining the number of charges q passing through a perpendicular cross-section of the conductor per unit time t. In equation form, it gives l = q/t

 • The unit of electric current is the ampere (A). It is equivalent

• The unit of electric current is the ampere (A). It is equivalent to 1 coulomb of charge passing through the conductor per second. 1 ampere= 1 coulomb/second • Conventional current is from the positive to negative terminal.

Conventional current is from the positive to negative terminal

Conventional current is from the positive to negative terminal

 • Generators in power plants produce alternating currents. This kind of current is

• Generators in power plants produce alternating currents. This kind of current is the household circuit. • In alternating current there is a continuous back and forth movement of electrons in the circuit. Ammeter- is used to measure current

Ammeter A Ammeter used to measure current

Ammeter A Ammeter used to measure current

Voltage • Is the quantity that determines the current in the circuit. • Electromotive

Voltage • Is the quantity that determines the current in the circuit. • Electromotive force (emf) – the energy transferred to one coulomb of charge within the battery. e. g a battery with a emf of 6 volts transfer 6 joules of energy to each coulomb of charge when the charge move through the battery.

 • Potential difference (pd) is the energy transferred to a circuit component per

• Potential difference (pd) is the energy transferred to a circuit component per unit charge. -Allesandro Volta- discovered voltage and volts(V) is named after him. 1 volt(v) = 1 joule/coulomb (C) 1 V=1 J/C Voltmeter use to measure voltage.

Voltmeter use to measure voltage

Voltmeter use to measure voltage

Conductors and Insulators • Resistance - this is the tendency of the wire to

Conductors and Insulators • Resistance - this is the tendency of the wire to resist the passage of electric current. It is measured in ohms Ω, named after George Ohm. • Conductors – materials with many loosely held electrons. • Insulators - materials that hold electrons tightly.

Insulators • Hard rubber • Dry air • Paraffin • Porcelain • Sulfur •

Insulators • Hard rubber • Dry air • Paraffin • Porcelain • Sulfur • Sealing wax • Glass • Dry silk • Bakelite and similar plastics Conductors • Metals • Earth • Moist materials • Water solution of salt • Human body.

How voltage, current, and resistance relate An electric circuit is formed when a conductive

How voltage, current, and resistance relate An electric circuit is formed when a conductive path is created to allow free electrons to continuously move. This continuous movement of free electrons through the conductors of a circuit is called a current, and it is often referred to in terms of "flow, " just like the flow of a liquid through a hollow pipe.

The force motivating electrons to "flow" in a circuit is called voltage. Voltage is

The force motivating electrons to "flow" in a circuit is called voltage. Voltage is a specific measure of potential energy that is always relative between two points. When we speak of a certain amount of voltage being present in a circuit, we are referring to the measurement of how much potential energy exists to move electrons from one particular point in that circuit to another particular point.

Free electrons tend to move through conductors with some degree of friction, or opposition

Free electrons tend to move through conductors with some degree of friction, or opposition to motion. This opposition to motion is more properly called resistance. The amount of current in a circuit depends on the amount of voltage available to motivate the electrons, and also the amount of resistance in the circuit to oppose electron flow.

1. A lamp, dry cell, and connecting wires are used in an electric circuit.

1. A lamp, dry cell, and connecting wires are used in an electric circuit. Which will supply the energy? A Lamp Only B Dry Cell Only C Connecting wires D Dry cell and lamp only

2. A 220 V electrical appliance is connected to a 220 V line. If

2. A 220 V electrical appliance is connected to a 220 V line. If the appliance is connected to a 110 V line, what happens to the current through it? A Remains the same B Reduced to one half C Doubled D Reduced to one-fourth

2. A 220 V electrical appliance is connected to a 220 V line. If

2. A 220 V electrical appliance is connected to a 220 V line. If the appliance is connected to a 110 V line, what happens to the current through it? A Remains the same B Reduced to one half C Doubled D Reduced to one-fourth

4. What relationship exist between current and voltage when resistance is kept constant? A

4. What relationship exist between current and voltage when resistance is kept constant? A Inverse Variation B Direct Variation C Equal D Complementary

5. Which of the following is consider a conductor of electricity? A Moist materials

5. Which of the following is consider a conductor of electricity? A Moist materials B Glass C Porcelain D Dry Silk

For your assignment answer A, from Nowpage kids, 27, thisexercise is the end of

For your assignment answer A, from Nowpage kids, 27, thisexercise is the end of our lesson. nos. 1 to 15

Mark Angelo R. Alcaide Fritzie Diane A. Razon Beverly Nikki S. Abanilla Iv-dandelion Proudly

Mark Angelo R. Alcaide Fritzie Diane A. Razon Beverly Nikki S. Abanilla Iv-dandelion Proudly presents Occidental mindoro E-Lesson presentation National high School ENERGY