How Capacitors Work

[Music] the capacitor is similar to a battery in that both store electrical energy the capacitor is a much simpler device that can't produce new electrons it only stores them however capacitors can do things a battery can't as we will show here for the purposes of this animation we'll focus on different parts of the current propagating through the wires at different times when we close the switch electricity immediately runs throughout the circuits although the convention is to think of electrical current is moving from positive to negative electrons actually move from negative to positive as we represent here with yellow particles as you can see the battery is not much good at powering this motor to lift this place because it discharges gradually much more slowly than with a capacitor with the same charge here we'll learn why capacitor is much better suited to such a task than the battery like a battery the capacitor has two terminals positive and negative inside the capacitor the terminals connect the two metal plates separated by an insulator that keeps the plates from touching each other and allows them to hold opposite charges maintaining an electric field capacitors can be useful for storing and quickly discharging electricity so you can power for example an electric motor as we'll show here first we need to charge the capacitor by closing the switch we create a circuit that includes both the capacitor and the battery electrons flow from the battery to the capacitor where they are stored here a yellow glow represents the increasing charge held by the plate for every electron gained by that negative plate an electron is lost by the positive plate maintaining the capacitor in equilibrium here the red glow represents the positive charge held by the plate that increases with each parting electron the capacitor continues to charge until it attains the voltage of the battery charging it now that the capacitor is fully charged let's put all that stored energy to use by connecting it to a new circuit we can power small motor this electrical current powers the pulley to lift the weight until the charge dissipate the electrons on the capacitors negative terminal are drawn to its positive terminal they rush along the path that leads there straight through the motor let's watch this again [Music] even though the battery and the capacitor attempted this task with the same amount of charge only the capacitor successfully powers the motor lifting the weight because it discharges much more quickly this feature makes capacitor is useful for powering things that need a quick surge of energy such as flash bulbs and cameras and starter motors and audio amplifiers in your car [Music]

Channel: National MagLab

Views: 4,153,817

Rating: 4.8202891 out of 5

Keywords: science, maglab, Florida State University, FSU, NHMFL, magnet, lab, physics, research, power transfer, charge particles, electric current

Id: 5hFC9ugTGLs

Length: 3min 33sec (213 seconds)

Published: Mon Apr 24 2017