Electromagnetism

Stray current corrosion: Stray current is the current which occurs when conductors are placed between high magnetic or electric fields. Presence of stray currents over the PCB surface can generate corrosion problems. The below figure 5 shows severe corrosion damage to micro wave module for 24 GHz. This equipment is built in controlled conditions where water condensation is possible. After few hours of use, severe corrosion was seen on the surface. Figure 5. Stray current corrosion of a micro…

Rotor and touchdown bearing models Fig. 1 features the case study of the high-speed rotor. The photo was taken after manufacturing of the electric motor part, when the rotor was carried to the laboratory for an experimental modal analysis. During normal operation, the rotor is supported by AMBs. In the dropdown event, the rotor is in contact with touchdown bearings at both ends of the rotor. Fig. 1. Rotor under investigation. In this work, the finite element model of the rotor employs…

Abstract – Photocopiers make use of Toner (powder) to form the latent electrical image on the electrostatically charged drum. The paper has to slide over the drum during Xerography process and hence it picks up the toner. Vague issues cause the non-picking of toner particles (approximately 10%) and they are left over the drum. This non-picked toner is termed as Waste Toner (WT). As it adversely affects the quality of proceeding copies, this has to be removed from the drum. A cleaning blade made…

What is a circuit? How do they work? An electric circuit is a kind of path made up of wires that allows the flow of electrons. The circuit has to be made in a circular form, as the electrons must frequently move in a full loop, in which they will return to their original position and then complete the loop again. (“What is an electric circuit?”) The battery or another source of power provides the voltage, or ‘electrical push’, that makes the electrons move through the circuit. When the electrons…

1. What is the forbidden gap in semiconductors? One electron volt (eV) 2. At absolute zero temperature, semiconductor behaves as Insulator 3. Define electrical conductivity. Electrical conductivity is the ability to conduct an electric current. 4. What are the two types of charge carriers in semiconductors? Electrons and holes are the two types of charge carriers in semiconductor. 5. Define charge carrier. Charge carrier is a particle, which carries electric charge or electric current from one…

2 Copper is a good conductor of electricity. Copper is good conductor of electricity because it contains free electrons. Copper has one free electron per atom. The free electron concentration in copper is 8.5 x 1028 per m3. The electrons start flowing as soon as the switch is closed. But the electrons themselves travel much more slowly. So how does the current come on everywhere as soon as the switch is closed? It is because the free electrons are already spread throughout the wire. As soon as…

The four fundamental forces have been around before mankind. These forces shape the way we live and interact with the objects around us on a daily basis. These forces are so important, they are in existence throughout the entire universe. Black holes, the formation of planets, galaxies and stars are all because of gravity and these same celestial bodies have their own electromagnetic forces and the strong and weak nuclear forces are. Since everything in the universe is made of atoms, there is…

Michael Faraday was born on September 22, 1791 in the middle of a technological revolution. At age fourteen, he became an intern to a bookbinder. This gave him an opportunity to learn to read, this is where he began to cultivate his love for science. During this time as an intern for a bookbinder he learned a lot of about different science subjects and decided that one day he would write a book of his own. He became so fascinated that he started spending part of his paycheck on buying chemicals…

Benjamin Franklin is a famous scientist who changed the world with this kite experiment. His experiment is called "The Philadelphia Experiment". The lab itself was the study of the relationship between the electricity in the lightning and a lightning rod itself. Franklin's theory involved the lightning bolt neutralizing the total or even a piece of the charged storm cloud. The bolt would then send energy to the high lightning rod. In his experiment, the kit was in replacement of the rod.…

In all the stories electricity is a very important part of our lives. Electricity runs parts and even most of this world. Energy and electricity creates and produce jobs. In "Energy Story" it talks about how electricity effects our everyday lives. The story also talks how electricity works with other materials to created energy. Energy is all around you and everywhere you go. Energy powers many objects such as car batteries, an even your home. "Energy Story" also talks about how all matter…