0
Electrical Engineering
Electrical engineering is a field of engineering that deals with the study and application of electricity, electronics and electromagnetism.
23,056 Questions
What part in a circuit that produces potential difference?
The potential difference is provided by the power source, which can be a battery or some form of electric generator. Inside the source, electric charges are raised up a potential gradient, and they then give up their energy as they travel down the potential gradient in the circuit that is being supplied with energy.
What is the effect of temperature on hall coefficient of a lightly doped semiconductor?
hall coefficient of a lightly doped semiconductor will decrease with increase in temp as hall coefficient is inversely proportional to number density of charge carriers.
Do the grounding conductors and bonding conductors ever connect to a common point?
The grounded circuit conductors of the wiring system are terminated on a separate ground buss that is located in the circuit breaker section of the panel. This buss is bolted directly to the rear of the distribution panel's metal enclosure in the circuit breaker section of the distribution panel. This ground buss is at the same potential as the ground electrode conductor above because of the grounding screw that connects the neutral block to the metal enclosure. Code requires when wiring sub panels within the same building that the neutral block screw be taken out of the circuit and a separate ground wire be run directly from the main distribution panel. This is to prevent any short circuit currents from the sub panel traveling back on the sub panel feeder's neutral wire.
<<>>
In house wiring you have earth ground connect to the ground bus in the main electric panel. Your neutral bus is "bonded" to the Ground bus only at the main panel. When you run branch panels you do not connect neutral to ground in these branch panels, only the main panel. There is typically a screw in an electric panel where the bonding occurs.
What is the Current through a 4 Ohm Resistor with 20 Volts across it?
Ohms law states that V = I (current) x R
Rearranging for I, I = V / R
therefore I = 20 / 4 = 5 Amps
What is the material to make printed circuit board?
FR-4 glass-reinforced epoxy. In fact, FR-4 is the grade of the fiber.
Solenoid windings are coils of wire that are tightly wound in a helical shape, typically around a cylindrical core. When an electric current passes through these windings, they create a magnetic field, which can be used to perform mechanical work, such as moving a plunger in electromagnetic devices like solenoid valves and relays. The design and number of turns in the winding affect the strength of the magnetic field and the performance of the solenoid.
A zero-conductor is also known as a negative supply conductor.
Charge and volts which one is conductor?
Neither charge nor volts is a conductor. These are terms for electricity, the movement of electrons along a conductor. A conductor is the medium that carries the charge and a volt is the amount of electrical 'pressure' which is being carried.
A conductor is generally a wire of other copper (sometimes carbon, sometimes aluminum or some other metal) but could be any other material. could be anything resistor, capacitor, ac/dc converter, microchip etc. they all conduct electricity by the method above, altering the properties of the energy.
Jewellery usually consists of eithe rmetal on its own, or precious or semi-preciou sstones set in metal. Such items would not be insulators. Jewellery such as beads on string, or manmade or wooden items would be insulators.
Media can come in different forms, in computing media is referring to Compact Disks and USB devices which are classed as portable media devices. Music/pictures and videos are all types of media.
What is harmonic as applied to fourier series?
When we do a Fourier transformation of a function we get the primary term which is the fundamental frequency and amplitude of the Fourier series. All the other terms, with higher frequencies and lower amplitudes, are the harmonics.
Why must an LED always have a resistor connected in series with it?
An LED usually has a resistor connected in series with it because an LED (light emitting diode) is not linear in current to voltage (like a resistor) and has to be operated within specified current and voltage conditions. In most circuits the supply voltage is higher than the forward voltage of the LED so the LED would burn up from too much current without a current limiting resistor in series. The resistor sets the voltage and current to a good operating point (voltage and current) for the LED by dropping some voltage across it. The operating point varies depending on the size, type and manufacturer of an LED so the LED's data is used to select the right resistor size for a given voltage source.
What is the need and function of stirrer motor?
The role of stirrer is to stir with the goal to homogenize solutions, pastes, powders.
Why used star contactor half value then main and delta contactor in star delta starter?
This type of motor starting configuration is used to start large motors. The utility company's policy is to only let a certain three phase motor horsepower loads across the line starting. High horsepower loads draw high current which draws the line voltage down. This causes a small instantaneous brown out to which the utility company gets complaints about. To solve this problem, limit the horsepower load. Starting a delta motor in star configuration reduces the inrush current because the voltage applied to the motor is lower.
This technology is rapidly becoming old due to the new type of motor controllers on the market. Replacing the star delta starters is soft start controllers. The inrush current can be controlled so as to not make any voltage drop on the line. These controllers are different from VFD's which are expensive for this type of application. The main function of the soft start is to get the motor on line without any line disturbances.
What is the current running through resistor three of 30 ohms if the volts are 90 volts?
Ohm's Law: Current = Voltage divided by resistance
90 volts divided by 30 ohms = 3 amperes
Be careful if you try this, it is also 270 watts, so the resistor will get very, very hot. Also, since everything has a temperature coefficient, do not expect the resistance when hot to be the same as the resistance when cold.
When phase and neutral are glowing what is the problem in circuit?
There is more current flowing and the wire can not flow that much current.
You cannot convert kWh into watts (W).
You can say that 571 kW = 571,000 W. This is because k (kilo-) = 1,000.
A watt is a unit of power (1 joule per second). So a kilowatt (kW) is also a unit of power. Power is the rate at which energy is produced or consumed.
When you multiply 1 kW by time (h = hour) you obtain a kilowatt hour (kWh), which is a unit of energy.
Electricity utilities charge for the energy consumed, measured in kilowatt hours.
Does battery room reqire air colling system?
A battery room may not require cooling, but it will require low humidity -- and for that you may need a cooling system or air conditioner.
What is the telltale factor for ascertaining where faults in a cable lie?
Impedance.
Depending on the cable type, it may also be possible to use a device called a "reflectometer", which sends a pulse down the wire and calculates the distance based on how long it takes for the signal to bounce back. This type of device works best for coaxial type cable.
