(DOWNLOAD) "Energy and Momentum Considerations in an Ideal Solenoid (Report)" by Sami Mohammad Al-Jaber " Book PDF Kindle ePub Free
eBook details
- Title: Energy and Momentum Considerations in an Ideal Solenoid (Report)
- Author : Sami Mohammad Al-Jaber
- Release Date : January 01, 2010
- Genre: Engineering,Books,Professional & Technical,
- Pages : * pages
- Size : 73 KB
Description
1. Introduction The electromagnetic Poynting vector has long been of considerable interest over the years [1-9]. This is so because it is directly related to the electromagnetic (EM) energy flux and the electromagnetic linear momentum. In recent years, the role of EM linear momentum in total momentum balance has attracted the attention of many authors [10-16]. Furthermore, the EM energy flux carried by the Poynting vector has been the subject of many workers in the context of energy conservation in electromagnetic systems [17-21]. In recent years, it was shown that when a charged capacitor is connected to another uncharged identical one, exactly half the stored energy disappears after the equilibrium state is achieved. This also happens when a capacitor is charged by a battery, where only half the supplied energy is stored in the capacitor. This pedagogical problem has been a topic of interest by several authors [22-27]. When dealing with energy conservation in EM systems, one has to consider all the possible channels through which energy is transported through as the system transforms from an initial non-equilibrium to a final equilibrium state. For example, it was shown [23] that when charging a capacitor half the work done by the power source is stored in the capacitor while the other half is carried by the Poynting vector which crosses the surface of the connecting wires. The purpose of this paper is to shed some light on the dynamics of the electromagnetic momentum and the energy needed when an electromagnetic system transforms from non-equilibrium to equilibrium states. This gives a fruitful and an illustrative example to students in electrodynamics course and helps them for a deep understanding of basic concepts in the subject. To that end, we consider an infinitely long solenoid which is fed by a current that varies linearly in time for a time period T after which it reaches its final constant value. The paper is organized as follows: In Section 2, we consider the electromagnetic momentum. In Section 3, we examine electromagnetic energy. Section 4 is devoted for conclusions.