Electrical Engineering

Georg Simon Ohm was a German schoolmaster who discovered that for certain conductors, the ratio of voltage to current was constant for variations in voltage.

He thought that this applied to all conductors, but this is not the case. In fact, Ohm's Law applies to very few conductors and, then, only under very specific conditions.

A circuit having two or more paths connected across the source.

There is a lot of step by step procedure for creating pso program in a mat lab. Start with set a population size, set mutation rate, fraction of population kept, number of bits in each parameter, total number of bits and the population members that survived.

student where given materials to comeplete a circuit to turn on one light.The materials recieved were two wires,a AA battery,and various size of the light bulbs.What is the variable in the experiment.

For a shunt dc motor the rheostat would vary from zero ohms to a value that produces the required minimum field current, but rheostats are not common with shunt motors except as a crude way of controlling the speed.

Series dc motors normally use rheostats for starting, especially in trams etc. because the starting torque and current is very high. The rheostat resistance starts at a value equal to the supply voltage divided by the maximum allowable current drawn, and is reduced as the speed builds up.

Yes. You will need to supply each phase with a separate 110V supply line. However make sure that the motor is designed to run at that voltage. Running the motor on load at a lower voltage than that which is on the name plate is dangerous because the motor will try to compensate for the reduction in power due to the lower voltage by demanding higher currents from the source. This will either result in damaging the motor or control circuits or causing bodily harm to yourself or someone else. Good luck.

The melting point or boiling point ...................

A Cobra power inverter changes direct current (DC) to alternating current (AC). It takes battery power and inverts it so that common household appliances can use the power.

A noise generator produces electrical signals in both audio and video format. These are used for troubleshooting purposes in signal circuits for amplifiers and televisions.

One can purchase an Auto Transformer from websites like Mastech Power Supply, Amazon, Ali Express, RS-Online, eBay, Foster Transformer, Farnell and Alibaba.

List the factors that affect the voltage building in D.C generator.

Polar capacitors are acidic wet dielectric type capacitors which work only when there is a DC voltage present between its two leads in right polarity. Polar capacitors are ideally suited for a DC power supply ripple filter. When connected in wrong polarity, chemical reactions within a polar capacitor can cause them to blow up, often violently, causing injury to someone nearby. Most polar capacitors these days come with a safety valve to release internal pressure build up.

Non polar capacitors are usually dry types made of ceramic, mylar, polyester or any possible dry insulator as a dielectric. Two polar capacitors connected back to back also make a non-polar capacitor. They work well in all situations whether there is any DC voltage present between their leads or not. Non polar capacitors are often very large and impractical in most applications except where a small capacitance value is required.

Some good applications for non-polar capacitors are: an AC motor starter, an AC line spike filter and a crossover network. Since voltages across an AC motor or inside a speaker system consist only of pure AC, polar capacitors cannot be used in those cases.

Polarized capacitors are typically large devices known as electrolytic or tantalum type packages, used for filtering or stabilizing voltage sources, usually in DC type circuits. Construction of these is if I recall correctly, an aluminum foil called the anode (positive lead), separated by an oxide film with a dielectric material known as the cathode (negative lead), hence polarity.

Non-polarized are similar to polarized except the plates are similar metal.

Polarized caps are typically used in large voltage situations, such as DC line filtering to reduce noise related to uneven voltage levels after rectification from an AC source. Mainly measured in microfarads. Polarity is critical to these devices. They are marked with the voltage rating (usually double the circuit voltage used) as well as the farad marking.

non-polarized caps are typically used in low voltage situations, both AC and DC. Polarity is not critical. Measured in pico farads typically.

The ripple frequency of a half-wave rectifier is the same as the input frequency.

Contactors have movable contacts in them which are operated by the action of the solenoid that they are attached too. This solenoid is basically an electromagnet with a spring that resets the contacts to the open position when current is removed from the solenoid's coil/windings. When an electrical current is fed through the coil of the solenoid it creates a magnetic field; the force of the field is stronger than the opposing force of the restting spring thus the moving part of the solenoid which has the contacts attached to it, moves down completing the electrical circuit.

Contactors are usually used in cases where the voltages and currents levels to be used are way beyond the capacity of a normal switch. A common example would be as a direct on line starter for a large electrical motor, which usually have large starting current of up to 5-8 times the run current of the motor. It is also important to note that voltage used to energize the contactors coil can be much smaller than the actual voltage be conveyed by the contacts which feed the electrical load.

it will not work

No, you are billed for the energy used so in principle the voltage does not affect the cost. The equipment used is designed for a set voltage and cannot be used on a different voltage.

The reason to choose 480 v instead of 208 v would be based on the size of the site, and if there are distances of more than 300 ft involved in the power supply it might be economical to start with a 480 v system.

The choices are between 120/208 v and 277/480 v so that using the higher voltage will require the installation of 277 v lighting

becouse its have more input

This is the field consist with electricity, electronics & electromagnetism principles and make the applications using those principles....

To find the rated current output of the generator, you must divide 375 kV.A (not 'kva') by the machine's rated voltage.

A mixer/grinder is just that. It can mix ingredients for baking. It can also grind meats and vegetables to make things like sausage.

when your current transformer is over loaded make sure it turns back into a car and drives away

'Dielectric constant' is an archaic term for relative permittivity. They are one and the same.

That is 20.8 kVa but a 208 v single phase supply is very rare. 208 v is usually three-phase, with 120v between neutral and the live wires.