4.2 potential difference ( pd ) and power

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4.2 Potential difference ( pd ) and power Potential Difference: * is defined as the work done (or energy transfer) per unit char V (Volt) = B A + + If 1J of work is done in moving of positive charge from A to B t Pd is 1V 1V = 1 J / C

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4.2 Potential difference ( pd ) and power. Potential Difference: * is defined as the work done (or energy transfer) per unit charge. V (Volt) = W (work done, J) Q (charge, C). +. B. - PowerPoint PPT Presentation

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4.2 Potential difference ( pd ) and power

Potential Difference:

* is defined as the work done (or energy transfer) per unit charge

V (Volt) = W (work done, J) Q (charge, C)

B

A +

+

If 1J of work is done in moving 1 C of positive charge from A to B then the Pd is 1V

1V = 1 J / C

4.2 Potential difference ( pd ) and power

Potential Difference:

* is defined as the work done (or energy transfer) per unit charge

V (Volt) = W (work done, J) Q (charge, C)

B

A +

+

If 1J of work is done in moving 1 C of positive charge from A to B then the Pd is 1V

1V = 1 J / C

4.2 Potential difference ( pd ) and power

Potential Difference:

* is defined as the work done (or energy transfer) per unit charge

V (Volt) = W (work done, J) Q (charge, C)

B

A +

+

If 1J of work is done in moving 1 C of positive charge from A to B then the Pd is 1V

1V = 1 J / C

4.2 Potential difference ( pd ) and power

Potential Difference:

* is defined as the work done (or energy transfer) per unit charge

V (Volt) = W (work done, J) Q (charge, C)

B

A +

+

If 1J of work is done in moving 1 C of positive charge from A to B then the Pd is 1V

1V = 1 J / C

4.2 Potential difference ( pd ) and power

Potential Difference:

* is defined as the work done (or energy transfer) per unit charge

V (Volt) = W (work done, J) Q (charge, C)

B

A +

+

If 1J of work is done in moving 1 C of positive charge from A to B then the Pd is 1V

1V = 1 J / C

Voltage or pd:* is electrical pressure* causes current to flow* is measured in Volts (V) with a voltmeter in parallel

1.5 V 1.5 V

1.5 V

1.5 V 1.5 V 1.5 V

1.5 VV

Voltage or pd:* is electrical pressure* causes current to flow* is measured in Volts (V) with a voltmeter in parallel

1.5 V 1.5 V

1.5 V

1.5 V 1.5 V 1.5 V

1.5 VV

Voltage or pd:* is electrical pressure* causes current to flow* is measured in Volts (V) with a voltmeter in parallel

1.5 V 1.5 V

1.5 V

1.5 V 1.5 V 1.5 V

1.5 VV

Energy from a battery

e……..

w….

e…….

E……..

Voltages in series circuits

The cell gives electrical potential energy to each electron – even when not connected

* Work is done by an electron when passing through a component.* Some of the electron’s electrical potential energy is transferred to heat and light.* The work done per coulomb of charge is called the potential difference across the component

-- J J J

J

Energy from a battery

e……..

w….

e…….

E……..

Voltages in series circuits

The cell gives electrical potential energy to each electron – even when not connected

* Work is done by an electron when passing through a component.* Some of the electron’s electrical potential energy is transferred to heat and light.* The work done per coulomb of charge is called the potential difference across the component

-- J J J

J

Energy from a battery

e……..

w….

e…….

E……..

Voltages in series circuits

The cell gives electrical potential energy to each electron – even when not connected

* Work is done by an electron when passing through a component.* Some of the electron’s electrical potential energy is transferred to heat and light.* The work done per coulomb of charge is called the potential difference across the component

-- J J J

J

Energy from a battery

e……..

w….

e…….

E……..

V V

VVoltages in series circuits

Energy from a battery

e……..

w….

e…….

E……..

V

V V

3 V4

3 V4

1.5 VVoltages in series circuits

The higher the v……... of the battery the more energythe electrons can t………... to the bulbs.

The bulb f………. heats up. Some of this heat energy is transformed to l…... energy.

voltagetransferfilament

light

V

V V

Voltages in series circuits

V

V V

3.0 V

1.5 V 1.5 V

In a series circuit the voltage is shared across components

Voltages in series circuits

A

In a series circuit the voltage is shared across components

V V

3.0 V

1.5 V 1.5 V

V 0.2 A

Voltages in series circuits

A

In a series circuit the voltage is shared across components

V V

3.0 V V

V V

0.1 A

Voltages in series circuits

A

In a series circuit the voltage is shared across components

V V

3.0 V V

V V

3 V4

3 V4

3 V4

3 V4

0.1 A

Voltages in series circuits

A

In a series circuit the voltage is shared across components

V V

3.0 V V

V V

3 V4

3 V4

3 V4

3 V4

0.1 A

Voltages in series circuits

Each bulb adds more resistance to the series circuit.

The current flowing drops.The voltage across each bulb drops

Problem:

If 30 J of work is done when 5C of charge passes through a component,calculate the potential difference across the component.

V = 30 J = 6 V 5 C

V (Volt) = W (work done, J) Q (charge, C)

4.2 Potential difference ( pd ) and power

Problem:

If 30 J of work is done when 5C of charge passes through a component,calculate the potential difference across the component.

V = 30 J = 6 V 5 C

V (Volt) = W (work done, J) Q (charge, C)

4.2 Potential difference ( pd ) and power

EMF Electromotive force of a source of electricity:

* is defined as the electrical energy produced per unit charge passing through the source

4.2 Potential difference ( pd ) and power

W ( J) = (Volt) X Q ( C) Electrical energy

produced when charge Q moves through the source

For a component with

For a component with

For a component with

For a component with

For a component with

For a component with

For a component with