Charging a capacitor, Physics

Charging a capacitor:

In the diagram below, all of the resistance in the circuit is added together and shown as a single value R.

495_Charging a capictor.png

With S1 closed and S2 open, the capacitor will charge up.

Note that Kirchhoff's second law always applies, that is:

                   E  =  VR  +  VC

The charging sequence is as follows:

  • On closing S1, no current has yet flowed, the capacitor plates have no charge on them and hence, there is no voltage across it.
  • The whole of the applied voltage is developed across the resistor:

                   VR  =  E

  • The initial charging current is equal to the current through the resistor:  2110_Charging a capictor1.png

  • As C charges, the potential difference across it (VC) increases, opposing the applied voltage (E) so that the charging current is progressively reduced.
  • Finally the capacitor is fully charged (VC = E) and current ceases (consequently VR = O).
  • This sequence is shown graphically below.
    529_Charging a capictor2.png  

The curves are called 'exponential' curves and it can be seen that the slopes dVc/dt and dl/dt are progressively decreasing as time increases.

 

Posted Date: 9/13/2012 4:42:34 AM | Location : United States







Related Discussions:- Charging a capacitor, Assignment Help, Ask Question on Charging a capacitor, Get Answer, Expert's Help, Charging a capacitor Discussions

Write discussion on Charging a capacitor
Your posts are moderated
Related Questions
Object-Image Relationships Ray tracing for a thin lens showing the formation of a real image of an object.

a loaded cart has a mass of 227kg. if a 312n force acting at an angle of 30degree to the ground is applied. how much work is done in moving the cart 15meters?

Define the Newton's Law of Cooling Newton's Law of Cooling: A cup of hot chocolate has cooled from 92°C to 50°C after 12 min in a room at 22°C.  a) What is the value for k (

is average speed the magnitude of average velocity?justify your answer with a suitable example?

A train consists of a 4300-kg locomotive pulling two loaded boxcars. The first boxcar has a mass of 12,700 kg and the second has a mass of 16,300 kg. Presume that the boxcar wheels

In the figure below the closed surfaces A and B appear as closed curves. Find the flux through closed surface B.

Wave motion is the phenomenon in which the particle/matter ruins at the point where it is.  But the disturbance/energy get transferred from one point to the other.  The particle ju

Combination of Resistance: In electric circuits the resistors are interlinked in two ways. Resistance in Series Resistance in Parallel

Explain the term 'dielectric constant' of a medium in terms of capacitance of a capacitor. Draw a graph showing variation of resistivity of carbon with temperature

Simultaneity principle The principle that all of the frames of reference will have invariant simultaneity; i.e., two events perceived as simultaneous (that is, having the simi