Electrical Engineering

No, a cellphone speaker cannot emit a high frequency tone powerful enough to kill a person. High frequency tones emitted by cellphones are limited in power and intensity and are not harmful to humans.

A phase in a three-phase busway is typically identified by the color red. This color coding helps to easily distinguish between the different phases and prevent errors during installation and maintenance.

Yes you can. Please be aware you have the situation of pulling more amps, in this case 5 amps, over the timmer before the fuse blows. which may damage the timer To avopid this appliances plugged into the timer should be rated at 15 amps or less. Thgere are different type circuit breaker immediate and time delay for where an appliance such as motors exceed the limit to start then drop down when running?

Hz is short for Hertz, which is the international standard (SI) unit of frequency of an alternating current (AC) voltage. 50Hz means the voltage alternates 50 times per second, 60Hz obviously means 60 times/sec. 60Hz is the normal frequency of the incoming power lines in North America, while 50Hz is seen in many European countries. While convertors exist to use electric devices on a different voltage, convertors generally are not available to use 50Hz devices on a 60Hz power grid, or vice-versa. While some devices can be used on either, many others will not work or may even be damaged. Check with the manufacturer to be sure. Incidentally, since the unit of Hertz is named after the German physicist Heinrich Hertz, it is customary to capitalize the H. So 60Hz is considered correct, while 60hz is not.

When your house was wired the outlets were probably wired using the stab in terminals on the back of the outlets, these tend to cause trouble over time.Turn off the power and rewire the outlets using the binding screw terminals.By chance if the outlets are wired on the binding screws, inspect all for loose joints.You may have to inspect every box and outlet on this circuit to find the problem. I once had a customer who was having a similar problem and it only showed up while playing the stereo very loud.We determined that the vibration was causing the stab in terminals to loose contact,we removed every outlet and switch and reconnected all by using the binding screws and the problem went away.Hope this helps.

Backfiring and difficulty starting on a 390 Ford motor could be due to issues with the ignition system, such as faulty spark plugs, distributor cap, or ignition timing. It could also be caused by fuel-related problems, such as a clogged fuel filter or carburetor issues. It's recommended to check these components to diagnose and repair the problem.

An electric shared neutral is the white or negative wire that is shared between two electrical circuits on a basic single phase system. Most electrical devices use 120 volts and require a "hot" wire and a neutral wire to operate. Some larger devices use 240 volts and require two "hot" wires to operate. Two circuit breakers in an electrical panel can share one neutral wire as long as the breakers are not on the same "leg" of power. When looking at an electrical panel there are usually two "legs" of power feeding all the breakers, each leg has 120 Volts to ground, if the "legs" are combined you will have 240 Volts. A neutral wire can be shared by two circuits as long as the breakers are on separate "legs". If someone needed to add two circuits in their home, the could run what is called a 3-wire romex, It has a black wire, a red wire, a white wire and a ground wire. The white wire is the neutral for both the black and red 120 volt circuits, and the breakers for the new circuits would need to be on separate "legs" in the panel.

This could occur if the 120V supply is split-phase, where two 120V lines are 180 degrees out of phase with each other. When measuring from one of these lines to the other, you would see 240V. This is a common setup in residential electrical systems in the United States.

It has been stated that: "AC outlets have polarity specific outlets because some devices can be ruined if the device is plugged in backwards." Although this might be true in some sense, the most important reason is enhanced user safety. This is a very good question; one that deserves a good answer. It is true that most household "alternating current" devices may work with a reversible (two-prong) plug inserted either way. It simply doesn't matter which way the current is going at any given moment. Many devices still have two identical prongs. The "polarized" plug is for extra user safety (and a three-prong plug is even safer, see below). Two-prong devices may be eventually phased out of production in many countries. AC outlets have polarity-specific sockets because some devices can easily become dangerous if the polarized device is plugged in backwards. This happens when the switch or fuse inside the appliance is designed to disconnect only the "hot" and not the "neutral" wire when the device is switched off because it is cheaper than switches that disconnect both wires. The "neutral" wire is typically connected to ground at the main panel, so it is safer to use the switch to open the "hot" wire. Also, in lamps (and light fixtures), the neutral should be connected to the lamp shell for added safety, and this could also become dangerous if reversed; the socket shell could still be "hot" even when the switch is off (and the light is out). Without a polarized plug, you can't tell which wire the switch will disconnect and may receive a shocking surprise! In theory, safe devices are designed to keep a user from touching either the hot or the neutral. In practice, if designers know which wires will be "hot" inside the device, they can take extra precautions to make sure they cannot break apart and electrify anything a user can touch. A broken "hot" wire can electrocute a user if he/she touches the metal enclosure and the user "completes" the circuit to ground. Therefore, many appliances now have a polarized plug so the switch always disconnects the "hot" circuit and extra attention is placed on safe disconnection and insulation of that conductor throughout the device. A so-called "double-insulated" (IEC Class II) device may have a non-polarized plug because the same safe design has been made for BOTH conductors, regardless of which one may be "hot", and without relying upon a third prong for safety ground of the enclosure. No single internal fault would be likely to cause an electrocution hazard. Furthermore, even with a polarized plug, a single internal fault can be deadly in an ordinary appliance. The third prong (ground) can save your life if there is an internal fault of the hot touching exposed metal, and a GFCI can save your life if there is an internal fault of the neutral to exposed metal (where you could otherwise become the missing "neutral" connection to ground as you are electrocuted).

It has no resistance to a electric current

The term double-throw means that the operator can place or "throw" the switch into two different positions. One position feeds power from the utility system to the load. The other position feeds power from the standby generator to the load. Such a switch will prevent electricity, generated by the standby unit, to flow simultaneously to both the customer's home or farmstead, and to the utility's system.

Let's retool this one. Watts is volts times amps. Check. Amps produce heat and not the volts. Now hold on just a minute there, partner. Heat is power. Power is watts. It's volts times amps. Power = Watts = Heat. So "amps produce heat and not the volts" is misleading. Amps and volts together produce heat, produce watts, produce power. It's true that more amps through a given resistance produces more heat than less amps through that same resistance. But it doesn't apply here. The lamps operate on different voltages and draw different amounts of current (and have different resistances). But they both deliver the same power.

The answer is right in front of us. Both lamps are rated at 20 watts. Both produce 20 watts of heat. Assuming similar incandescent lamp types, both will have the same brightness, and both will generate the same amount of heat. No math required.

Hire an electrician. While unintentional, the clearest statement of your question is that you don't know what you are doing. You want your over-current protection device to be the weakest link in your system, so it pops before anything is damaged. You're talking about hooking a 50A line up to a 100A breaker, making the wiring the weakest link. That is a good recipie for a house fire.

The circuit breaker on a 2000 Ford Windstar is typically located in the fuse box under the hood or in the interior fuse panel. To test it, you can use a multimeter to check for continuity across the terminals. If there is no continuity or if the circuit breaker appears damaged, it may need to be replaced.

kVA is the unit for apparent power. Apparent power consists of active and reactive power. Active power is the share of the apparent power which transmits energy from the source (generator) to the user. Reactive power is the share of the apparent power which represents a useless oscillation of energy from the source to the user and back again. It occurs when on account of some »inertia« in the system there is a phase shift between voltage and current. This means that the current does not change polarity synchronous with the voltage. But the heat generated in a winding as well as the eddy current losses generated in a transformer core depend on the current only, regardless of whether it aligns with the voltage or not. Therefore the heat is always proportional to the square of the current amplitude, irrespective of the phase angle (the shift between voltage and current). So a transformer has to be rated (and selected) by apparent power. We define "complex power" as voltage times current (V*I), and thus the unit for power is the Volt-Amp (VA). When a circuit contains non-resistive elements (such as transformers), there is a component of power called "reactive power", which is power that is transmitted as a result of energy stored in inductors and capacitors. Reactive power does no useful work. Complex power is the sum of reactive power and real power (power which does work). When only real power is considered, the unit of power is the Watt. Transformers are rated in VA and not W because heat generated by electricity flowing through a conductor is proportional to the current flowing through the conductor. Although reactive power does no work, the current exists nonetheless and must be accounted for when selecting the proper sized wiring.

240 Volts uses both phases of the incoming service (each at 120 Volts and 180 degrees out of phase). Since the load is "balanced" there is no need for a separate "return" (when one phase is off the other is on). THAT IS WRONG!

The 240 volts measured between the two wires comes from a single phase, not two phases. [Two-phase is an industrial transmission and power system utilized in only two parts of the United States, and the two phases are 90 degrees out of phase with each other.]

Power flows in a circle, through the transformer windings and the load in series.

The "return" is a matter of perspective, depending which of the two wires you designate as the "source"! As neither of the "hot" wires in a 120/240 Volt system is grounded in the United States, it is a misconception to speak of one wire as if it were a high pressure hose, and the other a drain.

A short periodic low hum from a circuit breaker could indicate loose connections within the breaker or surrounding wiring, internal mechanical issues within the breaker itself, or electromagnetic interference affecting the breaker. It's recommended to have a qualified electrician inspect the breaker to determine the exact cause and address any potential safety hazards.

Have the utiliy company diconnect the power.

Good advice except they will probably cut your drops, and you will be without power for an extended period, especially if they are busy. Call a qualified electrician, they will most likely be able to give you some options, and prices over the phone at no cost. To be direct ELECTRICITY IS VERY DANGEROUS, and is best left to the trained and qualified who are familiar with the hazards it presents.

If only two wires are available for the circuit and the switch requires a neutral wire, you may need to run a new wire that includes a neutral to properly install the switch. It is important to ensure all wiring is done in accordance with local electrical codes to maintain safety. If unsure, consult a licensed electrician for assistance.

I would wonder if the items that are tripping the breaker are being plugged into the same outlet. There could be a problem with the outlet or the wiring in the box in the wall that the outlet is mounted in. If one of the screws on the back of the outlet that connects the wire to the outlet is loose, there would be a possibility of seeing your problem. Also, breakers can and do go bad. The more they pop, the more worn out they get. If you feel comfortable, you could try swapping the breaker in the box with another one of the same amp rating or just buy a new one since they aren't too expensive. You'll still have your old one as a spare or for an additional circuit to be added later. The TV could also act as a large capacitor and draw alot of current right when its turned on and charging up(like lights dimming when you turn something like a tv on)

Because the servo is electric, check the fuse panel for a blown fuse - there's a 25 amp fuse in your panel somewhere. The fuse is blown for a reason, ranging from an old fuse which is just "tired", to a "short" in the system, to a worn out servo. You might be lucky and stop at the fuse.

working principle of electrodynamometer is - when the same current passes through two concetric coils placed at right angles to each other,the resulting torque depends on the square of the current.

Electrodynamometer is used to construct various instruments like voltmeters,ammeters & also for constructing AC/DC wattmeters for any waveform of current & voltage.it is also used for frequency measurements & hormonic analysis.

Population inversion is necessary in laser action because it creates a higher number of atoms or molecules in an excited state than in the ground state, resulting in a larger number of photons being emitted through stimulated emission. This leads to the amplification of light, producing a coherent and intense laser beam. Without population inversion, there would be fewer photons available for amplification, limiting the efficiency and power of the laser.