Difference between revisions of "Potential Difference"
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==Key Stage 2== | ==Key Stage 2== | ||
===Meaning=== | ===Meaning=== | ||
− | '''Voltage''' is how much push electricity has. | + | '''Voltage''' is how much push [[electricity]] has. |
===About Voltage=== | ===About Voltage=== | ||
: The bigger the '''voltage''' the more push the [[electricity]] has to go around the [[circuit]]. | : The bigger the '''voltage''' the more push the [[electricity]] has to go around the [[circuit]]. | ||
− | : Adding another cell to the [[circuit]] in series will increase the '''voltage'''. | + | : Adding another [[Electrical Cell|cell]] to the [[circuit]] in series will increase the '''voltage'''. |
: With a bigger '''voltage''' a lamp will be brighter and a [[buzzer]] will be louder. | : With a bigger '''voltage''' a lamp will be brighter and a [[buzzer]] will be louder. | ||
Line 16: | Line 16: | ||
| style="height:20px; width:300px; text-align:center;" |A bulb will be brighter if the voltage is higher. | | style="height:20px; width:300px; text-align:center;" |A bulb will be brighter if the voltage is higher. | ||
|} | |} | ||
+ | |||
+ | ==Key Stage 3== | ||
+ | ===Meaning=== | ||
+ | [[Potential Difference]] is how much [[energy]] is [[Energy Transfer|transferred]] by a [[Electrical Current|current]]. | ||
+ | |||
+ | ===About Potential Difference=== | ||
+ | : '''Potential Difference''' is [[measure]]d using a [[Voltmeter]]. | ||
+ | : The [[SI Unit|units]] of '''potential difference''' are [[Volt]]s (V). | ||
+ | : '''Potential Difference''' is sometimes described as the 'push' that moves a [[Electrical Current|current]] around a [[circuit]]. | ||
+ | |||
+ | ==Key Stage 4== | ||
+ | ===Meaning=== | ||
+ | [[Potential Difference]] is the amount of [[energy]] [[Energy Transfer|transferred]] per unit [[Electrical Charge|charge]] between two points in a [[Electrical Circuit|circuit]]. | ||
+ | |||
+ | ===About Potential Difference=== | ||
+ | : '''Potential Difference''' is [[measure]]d using a [[Voltmeter]]. | ||
+ | : The [[SI Unit|units]] of '''potential difference''' are [[Volt]]s (V). | ||
+ | : '''Potential difference''' is the difference in '''potential''' between two points in a [[Electrical Circuit|circuit]]. | ||
+ | : '''Potential difference''' can be [[measure]]d between two points in a [[Electrical Circuit|circuit]] and is [[measure]]d across a [[Electrical Component|component]]. | ||
+ | : If two points in a [[Electrical Circuit|circuit]] are at the same '''potential''' there is no '''potential difference''' between them so no [[energy]] is [[Energy Transfer|transferred]] between those two points. | ||
+ | |||
+ | ===Equation=== | ||
+ | ''NB: You should remember this equation with energy transferred as the subject of the formula.'' | ||
+ | |||
+ | '''Charge''' = (Energy Transferred)/(Potential Difference) | ||
+ | |||
+ | <math>V=\frac{E}{Q}</math> | ||
+ | |||
+ | Where | ||
+ | |||
+ | <math>V</math> = The [[Potential Difference|potential difference]] between two points. | ||
+ | |||
+ | <math>Q</math> = The amount of [[Electrical Charge|charge]] that move between two points. | ||
+ | |||
+ | <math>E</math> = The [[Energy Transfer]]red by the '''charge'''. | ||
+ | |||
+ | ===Example Calculations=== | ||
+ | ====Finding Potential Difference from Charge and Energy Transferred==== | ||
+ | {| class="wikitable" | ||
+ | | style="height:20px; width: 300px; text-align:center;" |A '''charge''' of 84C transfers an [[energy]] of 20kJ. Calculate the [[Potential Difference|potential difference]] correct to two [[Significant Figures|significant figures]]. | ||
+ | | style="height:20px; width: 300px; text-align:center;" |170J of [[energy]] is transferred by a '''charge''' of 92mC. Calculate the [[Potential Difference|potential difference]] correct to two [[Significant Figures|significant figures]]. | ||
+ | |- | ||
+ | | style="height:20px; width: 300px; text-align:left;" |'''1. State the known quantities in correct [[unit]]s.''' | ||
+ | Q = 84C | ||
+ | |||
+ | E = 20kJ = 20x10<sup>3</sup>J | ||
+ | | style="height:20px; width: 300px; text-align:left;" |'''1. State the known quantities in correct [[unit]]s.''' | ||
+ | |||
+ | Q = 92mC = 92x10<sup>-3</sup>C | ||
+ | |||
+ | E = 170J | ||
+ | |- | ||
+ | | style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].''' | ||
+ | |||
+ | <math>V=\frac{E}{Q}</math> | ||
+ | |||
+ | <math>V=\frac{20 \times 10^3}{84}</math> | ||
+ | |||
+ | <math>V=238.0952V</math> | ||
+ | |||
+ | <math>V\approx 240V</math> | ||
+ | |||
+ | | style="height:20px; width:200px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers into the [[equation]] and [[Solve (Maths)|solve]].''' | ||
+ | |||
+ | <math>V=\frac{E}{Q}</math> | ||
+ | |||
+ | <math>V=\frac{170}{92 \times 10^{-3}}</math> | ||
+ | |||
+ | <math>V=1847.826V</math> | ||
+ | |||
+ | <math>V\approx 1800V</math> | ||
+ | |} | ||
+ | |||
+ | ====Finding Charge from Potential Difference and Energy Transferred==== | ||
+ | {| class="wikitable" | ||
+ | | style="height:20px; width:300px; text-align:center;" |The [[Potential Difference|potential difference]] of 12V is placed across a [[Electrical Resistor|resistor]] increasing its [[Thermal Energy Store|thermal energy store]] by 3.7J as a result. Calculate the '''charge''' that has flowed through the [[Electrical Resistor|resistor]] in this time correct to two [[Significant Figures|significant figures]]. | ||
+ | | style="height:20px; width:300px; text-align:center;" |A [[circuit]] transfers 2.8kJ of [[energy]] [[electrically]] to a [[motor]]. The [[Potential Difference|potential difference]] across the [[motor]] is 1.5V. Calculate the'''charge''' that has flowed through the [[motor]] in this time correct to two [[Significant Figures|significant figures]]. | ||
+ | |- | ||
+ | | style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities in correct [[unit]]s.''' | ||
+ | |||
+ | V = 12V | ||
+ | |||
+ | E = 3.7J | ||
+ | | style="height:20px; width:300px; text-align:left;" |'''1. State the known quantities in correct [[unit]]s.''' | ||
+ | |||
+ | V = 1.5V | ||
+ | |||
+ | E = 2.8kJ = 2.8x10<sup>3</sup>J | ||
+ | |- | ||
+ | | style="height:20px; width: 300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers and [[Evaluate (Maths)|evaluate]].''' | ||
+ | |||
+ | <math>V=\frac{E}{Q}</math> | ||
+ | |||
+ | <math>12=\frac{3.7}{Q}</math> | ||
+ | | style="height:20px; width: 300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers and [[Evaluate (Maths)|evaluate]].''' | ||
+ | <math>V=\frac{E}{Q}</math> | ||
+ | |||
+ | <math>1.5=\frac{2.8 \times 10^3}{Q}</math> | ||
+ | |- | ||
+ | | style="height:20px; width: 300px; text-align:left;" |'''3. [[Rearrange (Maths)|Rearrange]] the equation and [[Solve (Maths)|solve]].''' | ||
+ | |||
+ | <math>Q=\frac{3.7}{12}</math> | ||
+ | |||
+ | <math>Q=0.3083C</math> | ||
+ | |||
+ | <math>Q\approx0.31C</math> | ||
+ | | style="height:20px; width: 300px; text-align:left;" |'''3. [[Rearrange (Maths)|Rearrange]] the equation and [[Solve (Maths)|solve]].''' | ||
+ | |||
+ | <math>Q=\frac{2.8 \times 10^3}{1.5}</math> | ||
+ | |||
+ | <math>Q=1866.7C</math> | ||
+ | |||
+ | <math>Q\approx1900C</math> | ||
+ | |} | ||
+ | |||
+ | ====Finding Energy Transferred from Charge and Potential Difference==== | ||
+ | {| class="wikitable" | ||
+ | | style="height:20px; width: 300px; text-align:center;" |A bolt of lightning with a [[Potential Difference|potential difference]] 31,000kV transfers a '''charge''' of 15C. Calculate the [[Energy Transfer|energy transferred]] by this bolt of [[lightning]] correct to two [[Significant Figures|significant figures]]. | ||
+ | | style="height:20px; width: 300px; text-align:center;" |A 9V [[Electrical Battery|battery]] is able to mobilise a '''charge''' of 4.3kC during its operation. Calculate the total amount of [[energy]] stored in this [[Electrical Battery|battery]] correct to two [[Significant Figures|significant figures]]. | ||
+ | |- | ||
+ | | style="height:20px; width: 300px; text-align:left;" |'''1. State the known quantities in correct [[unit]]s.''' | ||
+ | |||
+ | V = 31,000kV = 3.1x10<sup>7</sup>V | ||
+ | |||
+ | Q = 15C | ||
+ | | style="height:20px; width: 300px; text-align:left;" |'''1. State the known quantities in correct [[unit]]s.''' | ||
+ | |||
+ | V = 9V | ||
+ | |||
+ | Q = 4.3kC = 4.3x10<sup>3</sup> | ||
+ | |- | ||
+ | | style="height:20px; width: 300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers and [[Evaluate (Maths)|evaluate]].''' | ||
+ | |||
+ | <math>V=\frac{E}{Q}</math> | ||
+ | |||
+ | <math>3.1 \times 10^7=\frac{E}{15}</math> | ||
+ | |||
+ | | style="height:20px; width: 300px; text-align:left;" |'''2. [[Substitute (Maths)|Substitute]] the numbers and [[Evaluate (Maths)|evaluate]].''' | ||
+ | |||
+ | <math>V=\frac{E}{Q}</math> | ||
+ | |||
+ | <math>9 =\frac{E}{4.3 \times 10^3}</math> | ||
+ | |- | ||
+ | | style="height:20px; width: 300px; text-align:left;" |'''3. [[Rearrange (Maths)|Rearrange]] the equation and [[Solve (Maths)|solve]].''' | ||
+ | |||
+ | <math>E = 15 \times 3.1 \times 10^7</math> | ||
+ | |||
+ | <math>E = 4.65\times10^8 J</math> | ||
+ | |||
+ | <math>E\approx4.7\times10^8 J</math> | ||
+ | |||
+ | | style="height:20px; width: 300px; text-align:left;" |'''3. [[Rearrange (Maths)|Rearrange]] the equation and [[Solve (Maths)|solve]].''' | ||
+ | |||
+ | <math>E = 4.3 \times 10^3 \times 9</math> | ||
+ | |||
+ | <math>E = 38700J</math> | ||
+ | |||
+ | <math>E \approx 39000 \times 10^4J</math> | ||
+ | |} | ||
+ | |||
+ | |||
+ | ===References=== | ||
+ | ====AQA==== | ||
+ | |||
+ | :[https://www.amazon.co.uk/gp/product/1471851354/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851354&linkCode=as2&tag=nrjc-21&linkId=9012a0d354024419214fb3ad5ac44ba0 ''Potential difference (p.d), page 294, GCSE Combined Science Trilogy 1, Hodder, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Potential difference (p.d); current-potential difference graphs, pages 43-5, GCSE Physics, Hodder, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Potential difference (p.d); direct and alternating, page 50, GCSE Physics, Hodder, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Potential difference (p.d); in transformers, page 237, GCSE Physics, Hodder, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Potential difference (p.d); induced, pages 232-3, GCSE Physics, Hodder, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Potential difference (p.d.), page 39, GCSE Physics, Hodder, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1471851370/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851370&linkCode=as2&tag=nrjc-21&linkId=01c69b0ae058f809cf636033e6ba793e ''Potential difference (p.d.); in series and parallel circuits, pages 46-7, GCSE Physics, Hodder, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/0008158762/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158762&linkCode=as2&tag=nrjc-21&linkId=a0fffa35b3ea49a63404f6704e0df7cc ''Potential difference, page 185, GCSE Chemistry; Student Book, Collins, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10177 ''Potential difference, pages 180, 181, GCSE Combined Science; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac363 ''Potential difference, pages 24, 25, 96-98, GCSE Physics; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/0008158770/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158770&linkCode=as2&tag=nrjc-21&linkId=ec31595e720e1529e49876c3866fff6e ''Potential difference, pages 52-69, 71-77, 264-5, GCSE Physics; Student Book, Collins, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/019835939X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=019835939X&linkCode=as2&tag=nrjc-21&linkId=57e96876985fc39b1a3d8a3e3dc238b6 ''Potential difference, pages 54-55, 58-61, 64-65, 67-70, 224-229, GCSE Physics; Third Edition, Oxford University Press, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Potential difference, pages 62-67, 89, 90, GCSE Combined Science Trilogy; Physics, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Potential difference, pages 64-69, 92, 93, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10178 ''Potential difference; alternating, page 188, GCSE Combined Science; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10179 ''Potential difference; direct, page 188, GCSE Combined Science; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10180 ''Potential difference; energy transferred, page 190, GCSE Combined Science; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac364 ''Potential difference; energy transferred, page 33, GCSE Physics; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10182 ''Potential difference; in parallel circuits, page 186, GCSE Combined Science; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac365 ''Potential difference; in parallel circuits, page 29, GCSE Physics; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Potential difference; in parallel, pages 72, 73, GCSE Combined Science Trilogy; Physics, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Potential difference; in parallel, pages 74, 75, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10183 ''Potential difference; in series circuits, page 185, GCSE Combined Science; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac366 ''Potential difference; in series circuits, page 28, GCSE Physics; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Potential difference; in series, pages 68, 69, GCSE Combined Science Trilogy; Physics, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Potential difference; in series, pages 70, 71, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/0008158770/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158770&linkCode=as2&tag=nrjc-21&linkId=ec31595e720e1529e49876c3866fff6e ''Potential difference; induced, pages 258-60, GCSE Physics; Student Book, Collins, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Potential difference; induced, pages 303-306, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac367 ''Potential difference; induced, pages 96-98, GCSE Physics; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10181 ''Potential difference; I-V characteristics, page 183, GCSE Combined Science; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac368 ''Potential difference; I-V characteristics, page 26, GCSE Physics; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac369 ''Potential difference; measuring, page 106, GCSE Physics; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10184 ''Potential difference; measuring, page 239, GCSE Combined Science; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Potential difference; measuring, pages 235, 236, GCSE Combined Science Trilogy; Physics, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Potential difference; measuring, pages 331, 332, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10185 ''Potential difference; national grid, page 191, GCSE Combined Science; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac370 ''Potential difference; national grid, page 34, GCSE Physics; The Revision Guide, CGP, AQA ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/178294558X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294558X&linkCode=as2&tag=nrjc-21&linkId=f0dfb66dafcb0c6e9449e7b1a4ae1ac371 ''Potential difference; transformers, page 98, GCSE Physics; The Revision Guide, CGP, AQA ''] | ||
+ | |||
+ | ====Edexcel==== | ||
+ | |||
+ | :[https://www.amazon.co.uk/gp/product/1292120223/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120223&linkCode=as2&tag=nrjc-21&linkId=068ecf40278c32406a7f1c6e66751417 ''Potential difference (p.d.), pages 142-143, 174, GCSE Physics, Pearson Edexcel ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945741/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945741&linkCode=as2&tag=nrjc-21&linkId=30da4f2178da182547b62a7329d13b57 ''Potential difference, pages 184-187, GCSE Combined Science; The Revision Guide, CGP, Edexcel ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782948163/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948163&linkCode=as2&tag=nrjc-21&linkId=0fdbfd5dd397d6e24a9dfb250f08587f ''Potential difference, pages 221, 222, GCSE Physics, CGP, Edexcel ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945733/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945733&linkCode=as2&tag=nrjc-21&linkId=2a2dbec9db6bf5766c0458d908fa0a52 ''Potential difference, pages 71-74, GCSE Physics; The Revision Guide, CGP, Edexcel ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782948163/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948163&linkCode=as2&tag=nrjc-21&linkId=0fdbfd5dd397d6e24a9dfb250f08587f ''Potential difference; in parallel circuits, pages 235, 236, GCSE Physics, CGP, Edexcel ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782948163/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948163&linkCode=as2&tag=nrjc-21&linkId=0fdbfd5dd397d6e24a9dfb250f08587f ''Potential difference; induced, pages 280-283, GCSE Physics, CGP, Edexcel ''] | ||
+ | |||
+ | ====OCR==== | ||
+ | :[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Potential difference (p.d.), p ages 100-101, 130-134, 136-137, Gateway GCSE Physics, Oxford, OCR ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Potential difference (p.d.); Calculations, pages 113, Gateway GCSE Physics, Oxford, OCR ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Potential difference (p.d.); Graphs, pages 106-107, Gateway GCSE Physics, Oxford, OCR ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Potential difference (p.d.); In series circuit, pages 102-103, Gateway GCSE Physics, Oxford, OCR ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/0198359837/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359837&linkCode=as2&tag=nrjc-21&linkId=3c4229e8b023b2b60768e7ea2307cc6f ''Potential difference (p.d.); Measurement, pages 101, 259-260, 262, Gateway GCSE Physics, Oxford, OCR ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945679/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945679&linkCode=as2&tag=nrjc-21&linkId=a2db42f7b4bdf10cafaafa3bb9120940 ''Potential difference, page 95, Gateway GCSE Chemistry; The Revision Guide, CGP, OCR ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945695/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945695&linkCode=as2&tag=nrjc-21&linkId=ceafcc80bcad6b6754ee97a0c7ceea53 ''Potential difference, pages 176-182, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR ''] | ||
+ | :[https://www.amazon.co.uk/gp/product/1782945687/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945687&linkCode=as2&tag=nrjc-21&linkId=9a598e52189317a20311d7a632747bc9 ''Potential difference, pages 44-50, Gateway GCSE Physics; The Revision Guide, CGP, OCR ''] |
Latest revision as of 09:35, 30 November 2021
Contents
Key Stage 2
Meaning
Voltage is how much push electricity has.
About Voltage
- The bigger the voltage the more push the electricity has to go around the circuit.
- Adding another cell to the circuit in series will increase the voltage.
- With a bigger voltage a lamp will be brighter and a buzzer will be louder.
A series circuit with one cell and one bulb. | A bulb will be brighter if the voltage is higher. |
Key Stage 3
Meaning
Potential Difference is how much energy is transferred by a current.
About Potential Difference
- Potential Difference is measured using a Voltmeter.
- The units of potential difference are Volts (V).
- Potential Difference is sometimes described as the 'push' that moves a current around a circuit.
Key Stage 4
Meaning
Potential Difference is the amount of energy transferred per unit charge between two points in a circuit.
About Potential Difference
- Potential Difference is measured using a Voltmeter.
- The units of potential difference are Volts (V).
- Potential difference is the difference in potential between two points in a circuit.
- Potential difference can be measured between two points in a circuit and is measured across a component.
- If two points in a circuit are at the same potential there is no potential difference between them so no energy is transferred between those two points.
Equation
NB: You should remember this equation with energy transferred as the subject of the formula.
Charge = (Energy Transferred)/(Potential Difference)
\(V=\frac{E}{Q}\)
Where
\(V\) = The potential difference between two points.
\(Q\) = The amount of charge that move between two points.
\(E\) = The Energy Transferred by the charge.
Example Calculations
Finding Potential Difference from Charge and Energy Transferred
A charge of 84C transfers an energy of 20kJ. Calculate the potential difference correct to two significant figures. | 170J of energy is transferred by a charge of 92mC. Calculate the potential difference correct to two significant figures. |
1. State the known quantities in correct units.
Q = 84C E = 20kJ = 20x103J |
1. State the known quantities in correct units.
Q = 92mC = 92x10-3C E = 170J |
2. Substitute the numbers into the equation and solve.
\(V=\frac{E}{Q}\) \(V=\frac{20 \times 10^3}{84}\) \(V=238.0952V\) \(V\approx 240V\) |
2. Substitute the numbers into the equation and solve.
\(V=\frac{E}{Q}\) \(V=\frac{170}{92 \times 10^{-3}}\) \(V=1847.826V\) \(V\approx 1800V\) |
Finding Charge from Potential Difference and Energy Transferred
The potential difference of 12V is placed across a resistor increasing its thermal energy store by 3.7J as a result. Calculate the charge that has flowed through the resistor in this time correct to two significant figures. | A circuit transfers 2.8kJ of energy electrically to a motor. The potential difference across the motor is 1.5V. Calculate thecharge that has flowed through the motor in this time correct to two significant figures. |
1. State the known quantities in correct units.
V = 12V E = 3.7J |
1. State the known quantities in correct units.
V = 1.5V E = 2.8kJ = 2.8x103J |
2. Substitute the numbers and evaluate.
\(V=\frac{E}{Q}\) \(12=\frac{3.7}{Q}\) |
2. Substitute the numbers and evaluate.
\(V=\frac{E}{Q}\) \(1.5=\frac{2.8 \times 10^3}{Q}\) |
3. Rearrange the equation and solve.
\(Q=\frac{3.7}{12}\) \(Q=0.3083C\) \(Q\approx0.31C\) |
3. Rearrange the equation and solve.
\(Q=\frac{2.8 \times 10^3}{1.5}\) \(Q=1866.7C\) \(Q\approx1900C\) |
Finding Energy Transferred from Charge and Potential Difference
A bolt of lightning with a potential difference 31,000kV transfers a charge of 15C. Calculate the energy transferred by this bolt of lightning correct to two significant figures. | A 9V battery is able to mobilise a charge of 4.3kC during its operation. Calculate the total amount of energy stored in this battery correct to two significant figures. |
1. State the known quantities in correct units.
V = 31,000kV = 3.1x107V Q = 15C |
1. State the known quantities in correct units.
V = 9V Q = 4.3kC = 4.3x103 |
2. Substitute the numbers and evaluate.
\(V=\frac{E}{Q}\) \(3.1 \times 10^7=\frac{E}{15}\) |
2. Substitute the numbers and evaluate.
\(V=\frac{E}{Q}\) \(9 =\frac{E}{4.3 \times 10^3}\) |
3. Rearrange the equation and solve.
\(E = 15 \times 3.1 \times 10^7\) \(E = 4.65\times10^8 J\) \(E\approx4.7\times10^8 J\) |
3. Rearrange the equation and solve.
\(E = 4.3 \times 10^3 \times 9\) \(E = 38700J\) \(E \approx 39000 \times 10^4J\) |
References
AQA
- Potential difference (p.d), page 294, GCSE Combined Science Trilogy 1, Hodder, AQA
- Potential difference (p.d); current-potential difference graphs, pages 43-5, GCSE Physics, Hodder, AQA
- Potential difference (p.d); direct and alternating, page 50, GCSE Physics, Hodder, AQA
- Potential difference (p.d); in transformers, page 237, GCSE Physics, Hodder, AQA
- Potential difference (p.d); induced, pages 232-3, GCSE Physics, Hodder, AQA
- Potential difference (p.d.), page 39, GCSE Physics, Hodder, AQA
- Potential difference (p.d.); in series and parallel circuits, pages 46-7, GCSE Physics, Hodder, AQA
- Potential difference, page 185, GCSE Chemistry; Student Book, Collins, AQA
- Potential difference, pages 180, 181, GCSE Combined Science; The Revision Guide, CGP, AQA
- Potential difference, pages 24, 25, 96-98, GCSE Physics; The Revision Guide, CGP, AQA
- Potential difference, pages 52-69, 71-77, 264-5, GCSE Physics; Student Book, Collins, AQA
- Potential difference, pages 54-55, 58-61, 64-65, 67-70, 224-229, GCSE Physics; Third Edition, Oxford University Press, AQA
- Potential difference, pages 62-67, 89, 90, GCSE Combined Science Trilogy; Physics, CGP, AQA
- Potential difference, pages 64-69, 92, 93, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
- Potential difference; alternating, page 188, GCSE Combined Science; The Revision Guide, CGP, AQA
- Potential difference; direct, page 188, GCSE Combined Science; The Revision Guide, CGP, AQA
- Potential difference; energy transferred, page 190, GCSE Combined Science; The Revision Guide, CGP, AQA
- Potential difference; energy transferred, page 33, GCSE Physics; The Revision Guide, CGP, AQA
- Potential difference; in parallel circuits, page 186, GCSE Combined Science; The Revision Guide, CGP, AQA
- Potential difference; in parallel circuits, page 29, GCSE Physics; The Revision Guide, CGP, AQA
- Potential difference; in parallel, pages 72, 73, GCSE Combined Science Trilogy; Physics, CGP, AQA
- Potential difference; in parallel, pages 74, 75, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
- Potential difference; in series circuits, page 185, GCSE Combined Science; The Revision Guide, CGP, AQA
- Potential difference; in series circuits, page 28, GCSE Physics; The Revision Guide, CGP, AQA
- Potential difference; in series, pages 68, 69, GCSE Combined Science Trilogy; Physics, CGP, AQA
- Potential difference; in series, pages 70, 71, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
- Potential difference; induced, pages 258-60, GCSE Physics; Student Book, Collins, AQA
- Potential difference; induced, pages 303-306, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
- Potential difference; induced, pages 96-98, GCSE Physics; The Revision Guide, CGP, AQA
- Potential difference; I-V characteristics, page 183, GCSE Combined Science; The Revision Guide, CGP, AQA
- Potential difference; I-V characteristics, page 26, GCSE Physics; The Revision Guide, CGP, AQA
- Potential difference; measuring, page 106, GCSE Physics; The Revision Guide, CGP, AQA
- Potential difference; measuring, page 239, GCSE Combined Science; The Revision Guide, CGP, AQA
- Potential difference; measuring, pages 235, 236, GCSE Combined Science Trilogy; Physics, CGP, AQA
- Potential difference; measuring, pages 331, 332, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA
- Potential difference; national grid, page 191, GCSE Combined Science; The Revision Guide, CGP, AQA
- Potential difference; national grid, page 34, GCSE Physics; The Revision Guide, CGP, AQA
- Potential difference; transformers, page 98, GCSE Physics; The Revision Guide, CGP, AQA
Edexcel
- Potential difference (p.d.), pages 142-143, 174, GCSE Physics, Pearson Edexcel
- Potential difference, pages 184-187, GCSE Combined Science; The Revision Guide, CGP, Edexcel
- Potential difference, pages 221, 222, GCSE Physics, CGP, Edexcel
- Potential difference, pages 71-74, GCSE Physics; The Revision Guide, CGP, Edexcel
- Potential difference; in parallel circuits, pages 235, 236, GCSE Physics, CGP, Edexcel
- Potential difference; induced, pages 280-283, GCSE Physics, CGP, Edexcel
OCR
- Potential difference (p.d.), p ages 100-101, 130-134, 136-137, Gateway GCSE Physics, Oxford, OCR
- Potential difference (p.d.); Calculations, pages 113, Gateway GCSE Physics, Oxford, OCR
- Potential difference (p.d.); Graphs, pages 106-107, Gateway GCSE Physics, Oxford, OCR
- Potential difference (p.d.); In series circuit, pages 102-103, Gateway GCSE Physics, Oxford, OCR
- Potential difference (p.d.); Measurement, pages 101, 259-260, 262, Gateway GCSE Physics, Oxford, OCR
- Potential difference, page 95, Gateway GCSE Chemistry; The Revision Guide, CGP, OCR
- Potential difference, pages 176-182, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR
- Potential difference, pages 44-50, Gateway GCSE Physics; The Revision Guide, CGP, OCR