Electronics Engineering

Check the internet to see if your charger will automatically step down to 7.2V (not likely if the charger is not the same brand as the battery). If it does not step down then it is possible but *** not recommended ***. Overvolting can cause nasty caustic leaking of toxic chemicals from the battery.

There is no way to store AC voltages as such. A battery is a storage device so AC is converted to DC for storage. When AC fails the stored DC voltage is then changed back to AC through a device called an inverter. The inverter outputs a square waveform instead of a sinusoid waveform but most loads, such as a computer power supply that is connected to the UPS, can not tell the difference.

It has a very sharp reverse breakdown voltage curve and is not damaged by the reverse current, as some normal diodes might be.

A small signal NPN transistor used for general purpose audio amplifiers and switching.

Try a pair of 2n1613 NPN transistors arranged as a darlington pair, collectors common, and Q1e tied to Q2b. input is on Q1b, output from + to the collectors. Ckt has hi input Z, and the slight conductive nature of rain water from + to Q1base will forward bias the switch.

Lo tech- a bargan basement smoke alarm- bridge the test contacts with a wet finger and it should go off. If that works, just solder wires and run them outside close together on a board to detect rain.

Like most other countries, you will find that in England we use voltages ranging from almost zero to a few tens of kV, depending on the application. ;)

However, assuming you mean the voltage supplied by 3-pin 13A mains sockets (type G) then from 1 January 2004 the mains supply should be 230V (-6%, +10%), 50 Hz (±1%). ie a range of 216.2 - 253V. This replaced the UK's former specification which was 240V ±6% (ie a range of 225.6 - 254.4V). Some "shaver sockets", similar to round 2-pin sockets (type C) found in mainland Europe, will supply 110 V, but be careful since they often have a dual mode 110V/240V.

To wire a three phase compressor, you will need a motor starter( three pole contactor) with a motor overload device sized for the motor run current. A single or double pole pressure switch. This example is for 208 volts, coil on starter should be rated for 208 volts. Bring the three phase conductors to the top of the starter from the disconnect and land them in the wire terminals. Bring the three motor leads to the bottom of the starter and land them in the wire terminals. Go back to the top of the starter, land a wire in A phase terminal ( left Hand phase) with the wire that is already there(some starters have provisions for two wires) take this wire to the pressure switch and land on one side of the contact. Land another wire on the other side of the contact and go back to the starter and go the "coil" terminal on the starter. Go back to the top of the starter B phase terminal(center phase) land another wire there and go to the starter overload device terminal. When the pressure switch closes you should have 208 volts present on the starter coil and it should pull in. Once the pressure switch is satisfied the contacts will open and the starter will drop out.

It all depends on the machine PSU(Power Supply Unit), usually 80v-150v or as I have constructed before a 20v computer so it's the same as saying 'How long is a piece of string?'-

The Computer power supply takes in the 120-240 volts coming from the A/C outlet and reduces it to 18 volts D.C. to run the System board and peripheral's in the case, i.e. DVD ROM, CD ROM, HDD, Graphics card and CPU fan. Your monitor as well runs on 18 V.D.C. which is again reduced from the 120 - 240 volts A.C. through the power block, (transformer).

Zero crossing is commonly used in mathematics and electronics. Its when the mathematical function changes represented by crossing at an axis.

Actually electrical engineering comprises all the subjects basics like electronic,

management, mechanical,computer based subjects through this we can learn all the subjects basics clearly and it is more useful for higher education. the very main advantage of picking electrical engineering is we can able to study any subjects related to research or industrial oriented or business oriented etc.., in our PG. electrical engineering subject is also one of the toughest one in engg stream, if we pick electronic engg we go only by communication or electronic side so my answer is electrical has the upper hand than the electronic engg

* basic physics -- a voltage applied across a junction or an insulator will produce some current, no matter how small. No perfect insulator exists in electronics.

* defects in manufacturers -- undesirable elements in a junction or an insulator, introduced during manufacturing and stay, will affect the normal current-voltage behavior

* unintended usage -- the voltage or current applied to an electronic component has gone beyond its spec

* damage -- the electronic component has suffered permanent damage due to excessive usage, abuse, or electrostatic discharge.

It is a college where many usually MOST people don't live on dorms at the college but rather live with their parents and drive to school every day.

Most likely made by a robot machine. IE: more better it is maybe 30 feet of small copper or aluminum tubing wound in a back and forth coil pattern to fit the required area in the freezer. Metal fins may be attached to help move the cold into the freezer as air is blown over the coil.

voltage drop is zero bcz in open ckt current will be zero

A conductor is that one which allows the flow of electric current through it. An inductor is also a conductor but in the form of a coil used in varying current circuits. An inductor's role is not to conduct electricity; it is used in alternating current circuits and control it without much power loss. it is based on self induction.

pass AC voltages.

In a photo-diode when light is incident, the fractional increase in the majority carriers is much less than the fractional increase in the minority carriers. Consequently, the fractional change due to the photo-effects on the minority carrier dominated reverse bias current is more easily measurable than the fractional change due to the photo-effects on the majority carrier dominated forward bias current. Hence, photo-diodes are preferred to be used in the reverse bias condition to easily observe the variation of current with intensity.

Yes. As long as the speaker impedance is higher than the minimum rating for the amplifier, you are OK.

A room noise detector could serve as a burglar alarm during the night and when away from home, of course, if no noisy dogs or other pets. It could serve as a child protection device, near a door to the outside of the home or near a swimming pool gate to alert the adults of he child's presence near the pool, or a road with traffic.

.7v less than unity for DC operation but unity for AC.

Anything that uses electricity. For example, a light-bulb.

Yes it is. Most Sn (tin) materials as semiconductors are direct band gap materials. Silicon on the other hand is an indirect band gap material.

The secondary current is determined by the load, not by the transformer. For example, if the secondary voltage is 50 V and the load is 100 ohms, then the secondary current will be 0.5 A. If the load is 25 ohms, then the secondary current will be 2 A. It is important that a continuous secondary current doesn't exceed the rated secondary current of the transformer.

because charge carriers are depleted there, some electrons from n side have fallen into holes on p side reducing/depleting carriers on both sides.

50 ohms...!