Capacitor - Revision history

Jmdonev: 1 revision imported: Doing upload, largely of old redirects.

2018-06-04T16:52:30Z

1 revision imported: Doing upload, largely of old redirects.

← Older revision	Revision as of 16:52, 4 June 2018
(No difference)

Jmdonev at 21:24, 1 June 2018

2018-06-01T21:24:44Z

← Older revision		Revision as of 21:24, 1 June 2018
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	[[Category:Done 2018-04-30]]		[[Category:Done 2018-06-01]]
	[[File:Capacitor plates.JPG\|150px\|framed\|right\|Figure 1. Schematic of a capacitor, including two parallel plates with a surface area, A, and a separation distance, d. While not all capacitors are in this shape, they're often thought of as looking like this since it's the simplest geometry.]]		[[File:Capacitor plates.JPG\|150px\|framed\|right\|Figure 1. Schematic of a capacitor, including two parallel plates with a surface area, A, and a separation distance, d. While not all capacitors are in this shape, they're often thought of as looking like this since it's the simplest geometry.]]
	[[File:Capacitance.gif\|400px\|framed\|right\|Figure 2. An animation from a PhET simulation of a battery charging a capacitor until the current no longer flows through the circuit.<ref>University of Colorado. (April 25, 2015). ''Circuit Construction Kit'' [Online]. Available: http://phet.colorado.edu/sims/circuit-construction-kit/circuit-construction-kit-ac_en.jnlp</ref>]]		[[File:Capacitance.gif\|400px\|framed\|right\|Figure 2. An animation from a PhET simulation of a battery charging a capacitor until the current no longer flows through the circuit.<ref>University of Colorado. (April 25, 2015). ''Circuit Construction Kit'' [Online]. Available: http://phet.colorado.edu/sims/circuit-construction-kit/circuit-construction-kit-ac_en.jnlp</ref>]]
	<onlyinclude>A '''capacitor''' is an electronic device that stores [[charge]] and [[energy]]. Capacitors can give off energy much faster than [[batteries]] can, resulting in much higher [[energy density vs power density\|power density]] than batteries with the same amount of energy.</onlyinclude> Research into capacitors is ongoing to see if they can be used for storage of [[electrical energy]] for the [[electrical grid]]. While capacitors are old technology, [[supercapacitor]]s are a new twist on this technology.		<onlyinclude>A '''capacitor''' is an electronic device that stores [[charge]] and [[energy]]. Capacitors can give off energy much faster than [[battery\|batteries]] can, resulting in much higher [[energy density vs power density\|power density]] than batteries with the same amount of energy.</onlyinclude> Research into capacitors is ongoing to see if they can be used for storage of [[electrical energy]] for the [[electrical grid]]. While capacitors are old technology, [[supercapacitor]]s are a new twist on this technology.

	Capacitors are simply devices that consist of two conductors carrying equal but opposite charges. A simple parallel-plate capacitor consists of two equally-sized metal plates, known as electrodes, separated by an [[electrical insulation\|insulator]], known as a [[dielectric]], held parallel to each other. The capacitor is then integrated into an [[electric circuit]]. In a simple direct current circuit, each plate of the capacitor becomes oppositely charged over time due to the path of the [[electric current]] through the circuit. The battery drives charge in one direction such that one plate becomes positively charged and the other becomes negatively charged. This creates an electric field due to the buildup of equal and opposite charges, resulting in a potential difference, or [[voltage]] between the plates. Since the capacitance of the plates is constant, the voltage between the plates increases proportionally. As the charge on each plate increases, the voltage between the plates equals the voltage of the battery, at which point current will no longer flow through the circuit.<ref>HyperPhysics. (April 25, 2015). ''Capacitors'' [Online]. Available: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capac.html</ref> This charging and discharging effect can be seen in Figure 2. Current can resume flowing if an alternate path is opened so that the capacitors can discharge itself or by using an [[alternating current]] so that the capacitor is periodically charged and discharged.		Capacitors are simply devices that consist of two conductors carrying equal but opposite charges. A simple parallel-plate capacitor consists of two equally-sized metal plates, known as electrodes, separated by an [[electrical insulation\|insulator]], known as a [[dielectric]], held parallel to each other. The capacitor is then integrated into an [[electric circuit]]. In a simple direct current circuit, each plate of the capacitor becomes oppositely charged over time due to the path of the [[electric current]] through the circuit. The battery drives charge in one direction such that one plate becomes positively charged and the other becomes negatively charged. This creates an electric field due to the buildup of equal and opposite charges, resulting in a potential difference, or [[voltage]] between the plates. Since the capacitance of the plates is constant, the voltage between the plates increases proportionally. As the charge on each plate increases, the voltage between the plates equals the voltage of the battery, at which point current will no longer flow through the circuit.<ref>HyperPhysics. (April 25, 2015). ''Capacitors'' [Online]. Available: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capac.html</ref> This charging and discharging effect can be seen in Figure 2. Current can resume flowing if an alternate path is opened so that the capacitors can discharge itself or by using an [[alternating current]] so that the capacitor is periodically charged and discharged.

Jmdonev: 1 revision imported

2018-05-11T18:17:05Z

1 revision imported

← Older revision	Revision as of 18:17, 11 May 2018
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Jmdonev at 19:19, 9 May 2018

2018-05-09T19:19:09Z

← Older revision		Revision as of 19:19, 9 May 2018
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	[[Category:Done ~~2017~~-07-01]]		[[Category:Done 2018-04-30]]
	[[File:Capacitor plates.JPG\|150px\|framed\|right\|Figure 1. Schematic of a capacitor, including two parallel plates with a surface area, A, and a separation distance, d. While not all capacitors are in this shape, they're often thought of as looking like this since it's the simplest geometry.]]		[[File:Capacitor plates.JPG\|150px\|framed\|right\|Figure 1. Schematic of a capacitor, including two parallel plates with a surface area, A, and a separation distance, d. While not all capacitors are in this shape, they're often thought of as looking like this since it's the simplest geometry.]]
	<onlyinclude>A '''capacitor''' is an electronic device that stores [[charge]] and [[energy]]. Capacitors can give off energy much faster than [[batteries]] can, ~~giving them~~ much higher [[energy density vs power density\|power density]] than batteries with the same amount of energy.</onlyinclude> Research into capacitors is ongoing to see if they can be used for storage of [[electrical energy]] for the [[electrical grid]]. While capacitors are old technology, [[supercapacitor]]s are a new twist on this technology.		[[File:Capacitance.gif\|400px\|framed\|right\|Figure 2. An animation from a PhET simulation of a battery charging a capacitor until the current no longer flows through the circuit.<ref>University of Colorado. (April 25, 2015). ''Circuit Construction Kit'' [Online]. Available: http://phet.colorado.edu/sims/circuit-construction-kit/circuit-construction-kit-ac_en.jnlp</ref>]]
			<onlyinclude>A '''capacitor''' is an electronic device that stores [[charge]] and [[energy]]. Capacitors can give off energy much faster than [[batteries]] can, resulting in much higher [[energy density vs power density\|power density]] than batteries with the same amount of energy.</onlyinclude> Research into capacitors is ongoing to see if they can be used for storage of [[electrical energy]] for the [[electrical grid]]. While capacitors are old technology, [[supercapacitor]]s are a new twist on this technology.

	Capacitors are simply devices that consist of two conductors carrying equal but opposite charges. A simple parallel-plate capacitor consists of two equally-sized metal plates, known as electrodes, separated by an [[electrical insulation\|insulator]], known as a [[dielectric]], held parallel to each other. The capacitor is then integrated into a [[circuit]]. In a simple direct current circuit, each plate of the capacitor becomes oppositely charged over time due to the path of the [[current]] through the circuit. The battery drives charge in one direction such that one plate becomes positively charged and the other becomes negatively charged. This creates an electric field due to the buildup of equal and opposite charges, resulting in a potential difference, or [[voltage]], between the plates. Since the capacitance of the plates is constant, the voltage between the plates increases proportionally as the charge on each plate increases ~~until~~ the voltage between the plates equals the voltage of the battery, at which point current will no longer flow through the circuit.<ref>HyperPhysics. (April 25, 2015). ''Capacitors'' [Online]. Available: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capac.html</ref> This charging and discharging effect can be seen in Figure 2. Current can resume flowing if an alternate path is opened so that the capacitors can discharge itself or by using an [[alternating current]] so that the capacitor is periodically charged and discharged.		Capacitors are simply devices that consist of two conductors carrying equal but opposite charges. A simple parallel-plate capacitor consists of two equally-sized metal plates, known as electrodes, separated by an [[electrical insulation\|insulator]], known as a [[dielectric]], held parallel to each other. The capacitor is then integrated into an [[electric circuit]]. In a simple direct current circuit, each plate of the capacitor becomes oppositely charged over time due to the path of the [[electric current]] through the circuit. The battery drives charge in one direction such that one plate becomes positively charged and the other becomes negatively charged. This creates an electric field due to the buildup of equal and opposite charges, resulting in a potential difference, or [[voltage]] between the plates. Since the capacitance of the plates is constant, the voltage between the plates increases proportionally. As the charge on each plate increases, the voltage between the plates equals the voltage of the battery, at which point current will no longer flow through the circuit.<ref>HyperPhysics. (April 25, 2015). ''Capacitors'' [Online]. Available: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capac.html</ref> This charging and discharging effect can be seen in Figure 2. Current can resume flowing if an alternate path is opened so that the capacitors can discharge itself or by using an [[alternating current]] so that the capacitor is periodically charged and discharged.

	[[File:Capacitance.gif\|400px\|framed\|left\|Figure 2. An animation from a PhET simulation of a battery charging a capacitor until the current no longer flows through the circuit.<ref>University of Colorado. (April 25, 2015). ''Circuit Construction Kit'' [Online]. Available: http://phet.colorado.edu/sims/circuit-construction-kit/circuit-construction-kit-ac_en.jnlp</ref>]]

	An important parameter for a capacitor is the [[capacitance]], a measurement of the ability of an object to store charge. There are two main ways to calculate capacitance, using either the physical area of the plates or the voltage applied to the plates.
			An important parameter for a capacitor is the [[capacitance]], a measurement of the ability an object has to store charge. There are two main ways to calculate capacitance, using either the physical area of the plates or the voltage applied to the plates.

	==Energy in a capacitor==		==Energy in a capacitor==
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	==Uses==		==Uses==
	Capacitors do not have as high an [[energy density]] as batteries, meaning a capacitor cannot store as much energy as a comparable-sized battery. That said, the higher [[power]] capabilities of capacitors mean they are good for applications that require storing small amounts of energy, then releasing it very quickly. Le Mans Prototype race cars use capacitors to power electric motors in the front wheels. These capacitors are charged through [[regenerative braking]], and allow all-wheel drive and extra power when exiting corners.<ref>"Super-capacitors take charge in Germany" by Philip Ball, MRS Bulletin, Volume 37 Issue 09 2012. pp 802-803</ref>		Capacitors do not have as high an [[energy density]] as batteries, meaning a capacitor cannot store as much energy as a comparable-sized battery. That said, the higher [[power]] capabilities of capacitors mean they are good for applications that require storing small amounts of energy, then releasing it very quickly. ''Le Mans Prototype'' race cars use capacitors to power electric motors in the front wheels. These capacitors are charged through [[regenerative braking]], and allow all-wheel drive and extra power when exiting corners.<ref>"Super-capacitors take charge in Germany" by Philip Ball, MRS Bulletin, Volume 37 Issue 09 2012. pp 802-803</ref>

	Capacitors are also used in many electronic devices that require a battery. This capacitor stores energy to prevent a loss of memory while the battery is being changed. A common (although not necessarily widely known) example is a camera flash charging. This is why ~~one~~ can't ~~take two pictures~~ with a flash in rapid succession; the capacitor must build up the energy from the battery.<ref>(2014, Jun. 27). ''How Camera Flashes Work'' [Online]. Available: http://electronics.howstuffworks.com/camera-flash.htm</ref>		Capacitors are also used in many electronic devices that require a battery. This capacitor stores energy to prevent a loss of memory while the battery is being changed. A common (although not necessarily widely known) example is a camera flash charging. This is why two pictures can't be taken with a flash in rapid succession; the capacitor must build up the energy from the battery.<ref>(2014, Jun. 27). ''How Camera Flashes Work'' [Online]. Available: http://electronics.howstuffworks.com/camera-flash.htm</ref>

	~~As well~~, capacitors play a key role in many practical circuits, primarily as current stabilizers and as components to aid in the conversion of [[alternating current]] to [[direct current]] in [[AC adapter]]s. They are able to be used in this way due to the fact that capacitors are resistant to sudden changes in voltage, meaning that they have the ability to act as a buffer to store and withdraw electrical energy to maintain a stable output of current.<ref>Sparkfun. (April 25, 2015). ''Capacitors'' [Online]. Available: https://learn.sparkfun.com/tutorials/capacitors</ref> Thus the capacitor is able to stabilize the fluctuating AC current by it's ability to hold and release electrical energy at different times.		Moreover, capacitors play a key role in many practical circuits, primarily as current stabilizers and as components to aid in the conversion of [[alternating current]] to [[direct current]] in [[AC adapter]]s. They are able to be used in this way due to the fact that capacitors are resistant to sudden changes in voltage, meaning that they have the ability to act as a buffer to store and withdraw electrical energy to maintain a stable output of current.<ref>Sparkfun. (April 25, 2015). ''Capacitors'' [Online]. Available: https://learn.sparkfun.com/tutorials/capacitors</ref> Thus the capacitor is able to stabilize the fluctuating AC current by it's ability to hold and release electrical energy at different times.

	Since capacitors store energy in [[electric field]]s, some researchers are working on developing [[supercapacitor]]s in order to help with [[energy storage]]. This could prove useful in the transportation of energy or for storing and releasing energy from [[intermittent electricity\|intermittent source]]s such as [[wind]] and [[solar power]].		Since capacitors store energy in [[electric field]]s, some researchers are working on developing [[supercapacitor]]s in order to help with [[energy storage]]. This could prove useful in the transportation of energy or for storing and releasing energy from [[intermittent electricity\|intermittent source]]s such as [[wind]] and [[solar power]].

			==Phet Simulation==
			The [http://phet.colorado.edu/ University of Colorado] has graciously allowed us to use the following Phet simulation. Explore this simulation to see how gravitational potential energy and spring potential energy go back and forth and create a changing amount of kinetic energy (hint: click '''show energy''' before hanging a [[mass]]):

			<html>
			<iframe src="https://phet.colorado.edu/sims/html/capacitor-lab-basics/latest/capacitor-lab-basics_en.html" width="800" height="600" scrolling="no" allowfullscreen></iframe>
			</html>

	==References==		==References==
	{{reflist}}		{{reflist}}
	[[Category:Uploaded]]		[[Category:Uploaded]]
	~~[[category: Mark edit]]~~

Jmdonev: 1 revision imported

2017-08-29T01:47:36Z

1 revision imported

← Older revision	Revision as of 01:47, 29 August 2017
(No difference)

Jmdonev at 06:20, 19 August 2017

2017-08-19T06:20:17Z

← Older revision		Revision as of 06:20, 19 August 2017
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	[[Category:Done ~~2015~~-09-05]]		[[Category:Done 2017-07-01]]
	[[File:Capacitor plates.JPG\|150px\|framed\|right\|Figure 1. Schematic of a capacitor, including two parallel plates with a surface area, A, and a separation distance, d. While not all capacitors are in this shape, they're often thought of as looking like this since it's the simplest geometry.]]		[[File:Capacitor plates.JPG\|150px\|framed\|right\|Figure 1. Schematic of a capacitor, including two parallel plates with a surface area, A, and a separation distance, d. While not all capacitors are in this shape, they're often thought of as looking like this since it's the simplest geometry.]]
	<onlyinclude>A '''capacitor''' is an electronic device that stores [[charge]] and [[energy]]. Capacitors can give off energy much faster than [[batteries]] can, giving them much higher [[energy density vs power density\|power density]] than batteries with the same amount of energy.</onlyinclude> Research into capacitors is ongoing to see if they can be used for storage of [[electrical energy]] for the [[electrical grid]]. While capacitors are old technology, [[supercapacitor]]s are a new twist on this technology.		<onlyinclude>A '''capacitor''' is an electronic device that stores [[charge]] and [[energy]]. Capacitors can give off energy much faster than [[batteries]] can, giving them much higher [[energy density vs power density\|power density]] than batteries with the same amount of energy.</onlyinclude> Research into capacitors is ongoing to see if they can be used for storage of [[electrical energy]] for the [[electrical grid]]. While capacitors are old technology, [[supercapacitor]]s are a new twist on this technology.
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	==Energy in a capacitor==		==Energy in a capacitor==
	The amount of energy stored by a capacitor is dependent on the capacitance and the voltage of the capacitor and is expressed as:		The amount of energy stored by a capacitor is dependent on the capacitance and the voltage of the capacitor and is expressed as:
	<center><m>E = \frac{C (\Delta V)^2} {2}</m></center>		<center><math>E = \frac{C (\Delta V)^2} {2}</math></center>
	:::* <m>\Delta V</m> is the voltage between the plates, measured in [[volt]]s (V)		:::* <math>\Delta V</math> is the voltage between the plates, measured in [[volt]]s (V)
	:::* <m>C</m> is the capacitance of the capacitor, measured in [[farad]]s (F)		:::* <math>C</math> is the capacitance of the capacitor, measured in [[farad]]s (F)
	:::* <m>E</m> is the energy stored in the capacitor, measured in [[joule]]s (J)		:::* <math>E</math> is the energy stored in the capacitor, measured in [[joule]]s (J)
	<br />		<br />
	Increasing the capacitance or the voltage or both increases the amount of energy stored in the capacitor.		Increasing the capacitance or the voltage or both increases the amount of energy stored in the capacitor.
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	{{reflist}}		{{reflist}}
	[[Category:Uploaded]]		[[Category:Uploaded]]
			[[category: Mark edit]]

J.williams: 1 revision imported

2015-09-03T18:22:48Z

1 revision imported

← Older revision	Revision as of 18:22, 3 September 2015
(No difference)

Jmdonev at 23:37, 28 August 2015

2015-08-28T23:37:51Z

← Older revision		Revision as of 23:37, 28 August 2015
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	[[Category:Done 2015-06-01]]		[[Category:Done 2015-09-05]]
	[[File:Capacitor plates.JPG\|150px\|framed\|right\|Figure 1. Schematic of a capacitor, including two parallel plates with a surface area, A, and a separation distance, d. While not all capacitors are in this shape, they're often thought of as looking like this since it's the simplest geometry.]]		[[File:Capacitor plates.JPG\|150px\|framed\|right\|Figure 1. Schematic of a capacitor, including two parallel plates with a surface area, A, and a separation distance, d. While not all capacitors are in this shape, they're often thought of as looking like this since it's the simplest geometry.]]
	<onlyinclude>A '''capacitor''' is an electronic device that stores [[charge]] and [[energy]]. Capacitors can give off energy much faster than [[batteries]] can, giving them much higher [[energy density vs power density\|power density]] than batteries with the same amount of energy.</onlyinclude> Research into capacitors is ongoing to see if they can be used for storage of [[electrical energy]] for the [[electrical grid]]. While capacitors are old technology, [[supercapacitor]]s are a new twist on this technology.		<onlyinclude>A '''capacitor''' is an electronic device that stores [[charge]] and [[energy]]. Capacitors can give off energy much faster than [[batteries]] can, giving them much higher [[energy density vs power density\|power density]] than batteries with the same amount of energy.</onlyinclude> Research into capacitors is ongoing to see if they can be used for storage of [[electrical energy]] for the [[electrical grid]]. While capacitors are old technology, [[supercapacitor]]s are a new twist on this technology.
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	As well, capacitors play a key role in many practical circuits, primarily as current stabilizers and as components to aid in the conversion of [[alternating current]] to [[direct current]] in [[AC adapter]]s. They are able to be used in this way due to the fact that capacitors are resistant to sudden changes in voltage, meaning that they have the ability to act as a buffer to store and withdraw electrical energy to maintain a stable output of current.<ref>Sparkfun. (April 25, 2015). ''Capacitors'' [Online]. Available: https://learn.sparkfun.com/tutorials/capacitors</ref> Thus the capacitor is able to stabilize the fluctuating AC current by it's ability to hold and release electrical energy at different times.		As well, capacitors play a key role in many practical circuits, primarily as current stabilizers and as components to aid in the conversion of [[alternating current]] to [[direct current]] in [[AC adapter]]s. They are able to be used in this way due to the fact that capacitors are resistant to sudden changes in voltage, meaning that they have the ability to act as a buffer to store and withdraw electrical energy to maintain a stable output of current.<ref>Sparkfun. (April 25, 2015). ''Capacitors'' [Online]. Available: https://learn.sparkfun.com/tutorials/capacitors</ref> Thus the capacitor is able to stabilize the fluctuating AC current by it's ability to hold and release electrical energy at different times.

	Since capacitors store energy in [[electric field]]s, some researchers are working on developing [[supercapacitor]]s in order to help with [[energy storage]]. This could prove useful in the transportation of energy or for storing and releasing energy from [[intermittent electricity\|intermittent source]]s such as [[wind]] and [[solar]].		Since capacitors store energy in [[electric field]]s, some researchers are working on developing [[supercapacitor]]s in order to help with [[energy storage]]. This could prove useful in the transportation of energy or for storing and releasing energy from [[intermittent electricity\|intermittent source]]s such as [[wind]] and [[solar power]].

	==References==		==References==
	{{reflist}}		{{reflist}}
	[[Category:Uploaded]]		[[Category:Uploaded]]

J.williams: 1 revision imported

2015-08-26T21:30:53Z

1 revision imported

← Older revision	Revision as of 21:30, 26 August 2015
(No difference)

J.williams at 16:51, 12 August 2015

2015-08-12T16:51:38Z

New page

[[Category:Done 2015-06-01]]
[[File:Capacitor plates.JPG|150px|framed|right|Figure 1. Schematic of a capacitor, including two parallel plates with a surface area, A, and a separation distance, d. While not all capacitors are in this shape, they're often thought of as looking like this since it's the simplest geometry.]]
<onlyinclude>A '''capacitor''' is an electronic device that stores [[charge]] and [[energy]]. Capacitors can give off energy much faster than [[batteries]] can, giving them much higher [[energy density vs power density|power density]] than batteries with the same amount of energy.</onlyinclude> Research into capacitors is ongoing to see if they can be used for storage of [[electrical energy]] for the [[electrical grid]]. While capacitors are old technology, [[supercapacitor]]s are a new twist on this technology.

Capacitors are simply devices that consist of two conductors carrying equal but opposite charges. A simple parallel-plate capacitor consists of two equally-sized metal plates, known as electrodes, separated by an [[electrical insulation|insulator]], known as a [[dielectric]], held parallel to each other. The capacitor is then integrated into a [[circuit]]. In a simple direct current circuit, each plate of the capacitor becomes oppositely charged over time due to the path of the [[current]] through the circuit. The battery drives charge in one direction such that one plate becomes positively charged and the other becomes negatively charged. This creates an electric field due to the buildup of equal and opposite charges, resulting in a potential difference, or [[voltage]], between the plates. Since the capacitance of the plates is constant, the voltage between the plates increases proportionally as the charge on each plate increases until the voltage between the plates equals the voltage of the battery, at which point current will no longer flow through the circuit.<ref>HyperPhysics. (April 25, 2015). ''Capacitors'' [Online]. Available: http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capac.html</ref> This charging and discharging effect can be seen in Figure 2. Current can resume flowing if an alternate path is opened so that the capacitors can discharge itself or by using an [[alternating current]] so that the capacitor is periodically charged and discharged.

[[File:Capacitance.gif|400px|framed|left|Figure 2. An animation from a PhET simulation of a battery charging a capacitor until the current no longer flows through the circuit.<ref>University of Colorado. (April 25, 2015). ''Circuit Construction Kit'' [Online]. Available: http://phet.colorado.edu/sims/circuit-construction-kit/circuit-construction-kit-ac_en.jnlp</ref>]]

An important parameter for a capacitor is the [[capacitance]], a measurement of the ability of an object to store charge. There are two main ways to calculate capacitance, using either the physical area of the plates or the voltage applied to the plates.

==Energy in a capacitor==
The amount of energy stored by a capacitor is dependent on the capacitance and the voltage of the capacitor and is expressed as:
<center><m>E = \frac{C (\Delta V)^2} {2}</m></center>
:::* <m>\Delta V</m> is the voltage between the plates, measured in [[volt]]s (V)
:::* <m>C</m> is the capacitance of the capacitor, measured in [[farad]]s (F)
:::* <m>E</m> is the energy stored in the capacitor, measured in [[joule]]s (J)
<br />
Increasing the capacitance or the voltage or both increases the amount of energy stored in the capacitor.

Alternatively, a [[dielectric]] can be added to the capacitor. A dielectric is an insulator placed between the electrodes. It increases the capacitance of the capacitor without needing to change its dimensions. This allows the capacitor to store more energy while still remaining small. How much of an increase is dependent to the material used for the dielectric.<ref>R. D. Knight, “Potential and Field,” in ''Physics for Scientists and Engineers: A Strategic Approach,'' 2nd ed. San Francisco: Pearson Addison-Wesley, 2008, ch. 30, sec. 5, pp. 922-932.</ref>

==Uses==
Capacitors do not have as high an [[energy density]] as batteries, meaning a capacitor cannot store as much energy as a comparable-sized battery. That said, the higher [[power]] capabilities of capacitors mean they are good for applications that require storing small amounts of energy, then releasing it very quickly. Le Mans Prototype race cars use capacitors to power electric motors in the front wheels. These capacitors are charged through [[regenerative braking]], and allow all-wheel drive and extra power when exiting corners.<ref>"Super-capacitors take charge in Germany" by Philip Ball, MRS Bulletin, Volume 37 Issue 09 2012. pp 802-803</ref>

Capacitors are also used in many electronic devices that require a battery. This capacitor stores energy to prevent a loss of memory while the battery is being changed. A common (although not necessarily widely known) example is a camera flash charging. This is why one can't take two pictures with a flash in rapid succession; the capacitor must build up the energy from the battery.<ref>(2014, Jun. 27). ''How Camera Flashes Work'' [Online]. Available: http://electronics.howstuffworks.com/camera-flash.htm</ref>

As well, capacitors play a key role in many practical circuits, primarily as current stabilizers and as components to aid in the conversion of [[alternating current]] to [[direct current]] in [[AC adapter]]s. They are able to be used in this way due to the fact that capacitors are resistant to sudden changes in voltage, meaning that they have the ability to act as a buffer to store and withdraw electrical energy to maintain a stable output of current.<ref>Sparkfun. (April 25, 2015). ''Capacitors'' [Online]. Available: https://learn.sparkfun.com/tutorials/capacitors</ref> Thus the capacitor is able to stabilize the fluctuating AC current by it's ability to hold and release electrical energy at different times.

Since capacitors store energy in [[electric field]]s, some researchers are working on developing [[supercapacitor]]s in order to help with [[energy storage]]. This could prove useful in the transportation of energy or for storing and releasing energy from [[intermittent electricity|intermittent source]]s such as [[wind]] and [[solar]].

==References==
{{reflist}}
[[Category:Uploaded]]