Electronics Engineering

Copper losses are energy losses from the windings, due to the currents passing through them. During an open-circuit test, there is no secondary current (so no secondary copper losses) and the primary current is very low (so the primary copper losses are minimum).

It depends on the resistance of each resistor. If each resistor, for example, is 0.333 ohm, then you could connect them in series. If each resistor, for example, is 3 ohms, then you could connect them in parallel.

according to the ohm's low if we increase the resistance the current decreases. As ohm's low states voltage is directly proportional to the current and resistance. So current can defined as the ratio of voltage to the resistance, as large the resistance, as low the current.

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Inductors are low pass devices, they conduct most easily at low frequencies. DC is the limiting case for low frequency AC: i.e. DC is the lowest possible AC frequency, zero Hz and thus conducts best through an inductor.

Capacitors are high pass devices, they conduct most easily at high frequencies. Infinite frequency AC is the limiting case for high frequency AC. Infinity Hz would conduct best through a capacitor.

Answering "What is differences between pld and mixed logic gatessuch as the 7400 7432 ic logic device name one pld device?"

negative tempareture

It depends on the reverse voltage. Up to about 5.6 volts, the zener has a negative temperature coefficient. Beyond 5.6 volts it begins to show a positive temperature coefficient.

A: A multimeter is an instrument design to measure ohms volts and amps. So to measure amps a shunt is provided to allow a sample of the current to be measured as a function of voltage.

1. Measure the box you're trying to wind.

2. Use wire and a variable tuning capacitor.

3. Wind as many turns as you need to to achieve the frequency range you want.

4. Connect the 2 lead to the variable tuning capacitor

5. Couple it to your radio.

6. Use about 1/2 turns for to connect a 300 ohm connection to your radios input.

More turns = Lower to mid range frequencies

Less turns = Mid to high frequencies.

In order to pass DC current through a transformer you would need some basic knowledge of what a transformer actually is.

A transformer is simply put a coil of copper wire around metal plates of iron.

When you put current onto the coil, the metal plates will build up a magnetic field.

During the build up of this magnetic field, the current will be 'low'

When the magnetic field is maximized, the coil will work as a shortcut on a DC power source.

In order to use a transformer, ie transform voltage up or down, we need a fluctuating magnetic field. This can not be done without electronics of some variety, and the resulting voltage will be AC, not DC.

The easiest way to use a transformer with a DC power source is to make a circuit that electronically change polarization of voltage back and forth. Depending on transformer, this can be as low as 50 times per second (EU standard 50 Hz AC 220 Volt, US standard 60 Hz AC 115 Volt) or higher like 100.000 times per second (100 Khz) as is in many high speed switch power supplies. It all depends on the transformer you use and what you want to use it for.

If say you want to make a power source for an electric drill and you want to use a car battery as the source, then I would forget it. An electric drill need a lot of juice and in order to do so via a transformer, this transformer would need to be very very large.

Every ampere of 12 Volt would only give you approx 0.07 Ampere of 115 Volt.

A drill easily drain 800 to 1000 Watts. Approx 8 Ampere at 115 Volt.

Following this, an ideal transformer with hardly any loss would eat away 100 Ampere every 8 ampere on output 115 Vac.

With the loss factor (some of the transformed voltage will be given away as heat) and you would probably need approx 110 Ampere 12 Volt in order to generate 8 Ampere 115 Vac. A normal 60-65 Ampere car battery would then last a mere half hour fully charged. Another problem is that most batteries are not designed for such a load over any prolonged time (more than 30-60 seconds).

Systems have been and are buildt that can withstand such a drain but they consist of many batteries connected in paralell in order to even the drain between all batteries.

The initials, IC, simply mean that the op-amp is made inside an integrated circuit. Op-amps have a total of 8 pins, and out of those 8 pins, 1 is inactive( pin no. 8) and 7 are active. 4 of the pins (2, 3, 4, and 7) supply the output, and one of the pins (pin 6) observes the output. So 7 means 7 active pins, 4 means 4 inputs, and 1 means 1 output.

The internal gain of an amplifier is the gain or the amplification factor of the transistor used in it....................it is internal because it is fixed for transistors while manufacturing..................

By connecting it to a circuit with the power still applied. Ohm meters work best when the component under test is removed from the circuit to eliminate parallel paths of current through other components.

The watt rating of a resistor is directly proportional to their physical size. Resistors generate heat just like any resistive load. Small resistors usually are rated at 1/4 watts, larger resistors about 1/4 in diameter have a 2 watt heat dissipation capacity. Ceramic wire wound resistors are wound on a tube form so that there is more surface area and cooling air can pass up through the tube. These types of resistors can dissipate up to 50 watts of unwanted heat.

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None. Resistors do not have watts.

Watts, ohms, amps, volts, farads... are all ways to measure electrical properties, and while there are interrelations, watts refer to the total amount of energy that a device consumes or produces.

It is positive and negative signal in the frequency of wave form, the voltage of amplitude modulation, that carriers the signal of frequency.In the process of graph showing result ...

The short answer is you need power. And power is the product of voltage and current: P = V*I. As either V or I approaches zero, P approaches zero. So, you need voltage and current flow to generate the power needed to operate an electrical circuit.

Yes, that's because the voltage output of an alternator is restricted by the number of windings that can be slotted into its armature, restricting its output voltage to just 25-30 kV, which is far too low for transmission purposes.

The simple answer is just decrease the current. However, if you are looking at doing it in a more controlled way, you could use Pulse Width Modulation (PWM) in part with an Arduino or other development board. You could also simply use a 555 Timer IC to simulate PWM.

THe mbile charger takes a.c (alternating current) from power source and convers it to d.c(direct current) and feds it to mobile battery.

The charger also steps down the voltage from the power line voltage 110v etc to very small voltages e.g3 v etc.

Simply test it with a multi meter. Set to DC and see if it is holding voltage. Then,...Set the meter on Ohms to check the continuity between the leads. If it shows little or no resistance, or doesnt beep, normally youre ok. If it beeps or shows resistance, its fried. Afterwards, since the voltage should have been drained by the meter on Ohms setting, see if it builds back up.