Queequeg said:A coil in a magnetic field produces a sinusoidal emf output, so why can't you just attach a capacitor to it to charge it? Is it simply because capacitors store energy in electric fields, so you would need an inductor?
berkeman said:A parallel LC circuit immersed in a changing B-field will indeed develop an AC voltage across the capacitor. Why would you think it would not?
Queequeg said:Hmm that would work and got me thinking, so besides an LC circuit could one also implement a rectifier diode for unidirectional current instead of the sinusoidal wave?
A capacitor is an electronic component that stores electrical energy in the form of an electric field. It consists of two conductive plates separated by an insulating material, also known as a dielectric. When a voltage is applied, one plate becomes positively charged while the other becomes negatively charged, creating an electric field between them. This process is known as charging. When the voltage is removed, the capacitor retains the stored energy until it is discharged.
Capacitors and magnetic fields are related through the phenomenon of electromagnetic induction. When a changing magnetic field passes through a capacitor, it induces a voltage across the plates, causing it to become charged. Similarly, when a capacitor is discharged, it produces a changing magnetic field around it. This relationship is important in many electronic devices, such as transformers and motors.
Capacitors are commonly used in electronic circuits to filter out unwanted noise and to smooth out voltage fluctuations. They can also be used to store energy and release it in a controlled manner, as in flash cameras and defibrillators. Magnetic fields, on the other hand, are utilized in devices such as inductors and transformers to store and transfer energy. They are also used in electric motors and generators to convert electrical energy into mechanical energy.
While capacitors and magnetic fields are essential components in many electronic devices, they can also be dangerous if not used properly. High voltage capacitors can store a significant amount of energy, and if not discharged properly, they can cause electric shock. Magnetic fields, especially strong ones produced by powerful electromagnets, can also be hazardous to human health and can interfere with electronic devices. It is important to handle these components with caution and follow proper safety protocols.
The capacitance of a capacitor can be calculated by dividing the charge on one plate by the potential difference between the plates. It is also affected by the area of the plates, the distance between them, and the type of dielectric material used. The strength of a magnetic field can be calculated using the formula B = μI/2πr, where B is the magnetic field strength, μ is the permeability of the material, I is the current flowing through the wire, and r is the distance from the wire. These calculations are essential in designing and troubleshooting electronic circuits.