Voltage is the cause and current is its effect. Voltage is the potential difference between two points. When charges flow due to this potential difference, we say that current is flowing.
Voltage and current can be compared to a water reservoir with tubes connected to the outlet, the reservoir is the supply. Now, voltage is compared to the pressure of the water at the outlet of the reservoir, and current compared to the the volume of the water that flows through the tubes, the thicker and shorter the tubes, the less the resistance and larger the volume of water passing through the tubes. To measure voltage, a volt meter is connected across the output terminals of the supply; to measure current (in units of amperes), one of the wires connecting a circuit to to the supply is cut, and a ammeter is connected to the two ends; or if there is a switch in the circuit it can be switched off, and the current can be measured across the terminals of the switch. The best way to measure current is by using a clamp type ammeter.
Voltage (sometimes called electric potential difference) is the electrical driving force set up by an electric potential difference. There are several ways to create an electric potential difference, but in any case, it is voltage that causes current flow if there is some kind of circuit or current path to support the flow. Current or current flow is the actual movement of electrons through the branches of a circuit when voltage (the "motivational force" that causes current flow) is applied.
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current is nothing but flow of electic charges through a particular area.it is denoted by I.its unit is ampere.
V=IR by ohms law.
voltage
Voltage is the potential energy that makes the electrical current flow in a circuit by pushing the electrons around. The unit of voltage is volt shown as 'v'.
Think of voltage as a potential. A bunch of free electrons looking for someplace to go. The current is how they get there. If you think of a vat of water being a voltage and drilled a hole in the bottom the current would be the water flowing through the hole. The bigger the hole the higher the current (less resistance to the flow).
Voltage . . .
the difference in electrical 'pressure' between two points, that makes electrons want
to move from the higher-pressure point to the lower-pressure point if there's something
in between the two points for them to move through.
Under normal circumstances, there can easily be this difference in 'pressure'
between two points, but no electrons are moving across, because there's nothing
for them to move through. For example, there is substantial voltage between the
two slots in a household electrical outlet, but no way for electrons to move from
one to the other, until you plug something into the outlet that provides a path.
If the difference in pressure is great enough, then the electrons lose all reasoning
power and are consumed by an insane desire to make the trip even if there's nothing
there for them to move through, and they jump from one point to the other one anyway.
That's when you see a spark, or lightning.
Current . . .
When there's a path between the two points, then the electrons take off and move
from one point to the other. As long as the voltage is there, more and more electrons
step up and make the crossing. Current is simply the measurement of how heavy the
traffic is on the path ... how many electrons pass any point on the path every second.
If there happen to be about 6,241,000,000,000,000,000 electrons passing by in each
second, then we say that the current is "1 Ampere".
Greater current can be caused by either one of two conditions:
-- Greater voltage between the two points, inspiring more electrons to make the trip.
-- A path made of material that's easier for the electrons to travel in, such as
silver or copper ... the reason that electrical wiring is most often copper wire.
The arc utilized for arc welding is low voltage high current discharge. The voltage required for maintaining an arc is less than for striking the arc. Voltage drops & current increases as the arc is developed. The voltage required to strike DC arc is about 50-55 V & for AC is 80-90 V.It is difficult to maintain the arc with voltage less than 14V or more than 40V.READ ELECTRICAL TECHNOLOGY BY B L THAREJA / AK THAREJA
Current gain is the ratio of output current divided by input current. Voltage gain is the ratio of output voltage divided by input voltage. Nothing more complicated than that.
Parallel circuit: The fact that the voltage is the same follows from Kirchoff's Voltage Law. Series circuit: The voltages of the individual resistances must add up to the total voltage. This, too, follows from Kirchoff's Voltage Law. If the resistances have the same values, all of them will drop the same voltage (which, of course, will be less than the total resistance). But if they are different, Kirchoff's current law tells us that the same current must flow through each resistor in series - and the voltages will be different in this case, according to Ohm's law.
Reason: The common Emitter mode has voltage and current gain better than the other two configurations(CB and CC). i.e it has a current gain greater than that of CC mode and greater voltage gain than that of CB mode.
Unless otherwise stated, the value of an a.c. current or voltage is expressed in r.m.s. (root mean square) values which, for a sinusoidal waveform, is 0.707 times their peak value. The output of a voltage (or potential) transformer is no different, its measured voltage will be its r.m.s value which is lower than its peak value.
The "force" that pushes an electrical current is the voltage. It isn't really a force, but it may help to visualize it as such. Physically, it has different units than a force.
The "force" that pushes an electrical current is the voltage. It isn't really a force, but it may help to visualize it as such. Physically, it has different units than a force.
A reverse current relay prevents a generator from discharging the battery when generator output is less than battery voltage. When generator output is greater than battery voltage, the reverse current relay closes and connects generator to electrical bus.
yes they do! :) Europe uses a different voltage than the US and also has different shaped electrical plugs, so you can't just plug a European appliance into an American electrical outlet. If you can get the right kind of current, then the appliances will still work.
A reverse current relay prevents a generator from discharging the battery when generator output is less than battery voltage. When generator output is greater than battery voltage, the reverse current relay closes and connects generator to electrical bus.
Low voltage is a relative term, as there is no 'level' at which a voltage is rated 'low'. Electrical safety codes define low voltage as circuits that do not require the same protections necessary at higher voltages.
The arc utilized for arc welding is low voltage high current discharge. The voltage required for maintaining an arc is less than for striking the arc. Voltage drops & current increases as the arc is developed. The voltage required to strike DC arc is about 50-55 V & for AC is 80-90 V.It is difficult to maintain the arc with voltage less than 14V or more than 40V.READ ELECTRICAL TECHNOLOGY BY B L THAREJA / AK THAREJA
High voltage loads is a high electrical discharge that can result to electrical breakdown. Example: High power amplifier vacuum tubes or particle beams. High current loads are the loads that can have peak current greater than 10 amps. Example: Motors, solenoids or nitinol wire.
Current gain is the ratio of output current divided by input current. Voltage gain is the ratio of output voltage divided by input voltage. Nothing more complicated than that.
No, the electrical meter reads watts by multiplying the voltage and the amperage used in electrical circuits. Using oversize wire does not govern the amperage flow to the load. The load resistance in the circuit is what governs the amount of current that flows through the wire. This current in the load circuit is multiplied by the voltage applied to the circuit at the electrical meter. The product of this multiplication is wattage, multiplied by the amount of time the load is on, is what the electrical utility bill is based on.
i think the answer is more on economical reasons ( 220v in the phil ).. since Voltage is inversely proportional to current..the higher the voltage, the lower the current..the lower the current, the smaller the electrical cable to use. In short, if we used 220v, electrical cable to be used is much smaller compared to the cable used in 110v..Smaller cable means less price than of the much larger cable.. :))
A transformer. it steps up / down voltage, and steps down / up current.