Take your pick:
P = V x I (Power = Voltage x Current)
or:
P = V2 / R (Power = Voltage2 / Resistance)
or:
P = I2 *R (Power = Current2 x Resistance)
(the last two equations come from combining the ohms law equation R=V/I with the power equation P=VxI)
In the question above you have resistance and voltage therefore:
P = V2 / R = 92 / 900 = 0.090W = 90mW
(i believe 0.125W is the smallest resistor you can get)
hope that helps
A 10 ohm resistor across a 20 volt source has 2 amps flowing through it. A 20 volt source providing 2 amps is producing 40 watts. Voltage is Resistance times AmperesWatts is Voltage times AmperesAlternative AnswerDivide the square of the voltage by the resistance.
If a 9.0 volt battery is connected to a 4.0-ohm and 5.0-ohm resistor connected in series, the current in the circuit is 1.0 amperes. If a 9.0 volt battery is connected to a 4.0-ohm and 5.0-ohm resistor connected in parallel, the current in the circuit is 0.5 amperes.
The current would be about 20 volts.
Typically, a 100 ohm resistor is used to connect a 1.5 volt led to a series 220v ac adapter. Many LEDs can be connected into a string using the resistors.
It means 3.6 volt amps which is essentially 3.6 watts.
Ohms does not equal watts. You need to know what voltage is across the resistor to determine how many watts it is drawing or how many watts the resistor should be rated for.Power is the voltage across the resistor SQUARED divided by the resistance. If this 4 ohm resistor has 12 volts across it then the watts power is (12 x 12) / 4 = 36 watts.1 Watt equals 1 Volt times 1 Amp.
about 27ohms
The formula you are looking for is Watts = Amps x Volts. Amps = Watts/Volts. This comes to 4 amps load. Minimum size fuse would be 5 amps.
If there is nothing else in the circuit, then the voltage drop across the resistor will be the full supply voltage of 5 volts. The size of the resistor does not matter in this case - it will always be 5 volts.
If you connect a 100 ohm resistor across 120 volts it will draw 1.2 amps, amps = E/R. Power = volts x amps so the power required for the resistor would be 120 x 1.2 = 144 watts. It would not matter if the 120 volt circuit already has 2 amps load on it by something else to calculate the wattage of the resistor. The total power on this circuit would be the 144 watts from the resistor and 240 watts from the other 2 amp load (2a x 120v) for a total of 384 watts.
The resistor is 1/3 of an ohm. A 9 volt drop across the resistor would cause a draw of 27 amps through the resistor. The wattage you would need for that resistor is at least a 243 watts.
A 30 volt 90 watt lamp has 3 amps going through it. The series resistor also has 3 amps going through it, by Kirchoff's current law. The voltage across the resistor is 90 volts. With 3 amps, that is 30 ohms. (By the way... The resistor must be rated to carry 270 watts. That is a lot of power for a resistor.)
#16 <<>> To load an extension cord to 1725 watts depending on the length of the cord, the bare minimum should be #14. A better size cord and my recommendation would be a #12 wire size extension cord.
Sir, i will not go by watts because it can take many hundreds of watts per outlet but it also depend on the size of the wire in the outlet the bigger the number the more watts.
There is no way to make the conversion. The wattage given as that of the resistor is only the amount of power it is dissipating. It's the heat the resistor is radiating. The resistor is said to be using or radiating 270.4 watts. (That's a lot of wattage! How hot would a 270 watt incandescent lamp get? Very hot.) A watt is sometimes called a volt-amp. That's because watts equals volts times amps. And it's easy to see how that works with an example including the approximately 270 watts set down in the question. As regards that approximately 270 watts specified, if the resistor was a 1 ohm resistor and had 270 amps of current flowing through it, the 270 watts would be the wattage the resistor would be radiating. If the resistor was a 270 ohm resistor and had 1 amp of current flowing through it, it would (also) be radiating 270 watts. See how that works? An unlimited number of variations on the theme exist. To find the resistance of the resistor, one of two things must be known in addition to the wattage the resistor is running at. Either the voltage across the resistor or the current flow through the resistor must be specified to "finish" the problem.
The "size" (value or the power capacity) of the resistor can not be defined unless the power of the 3 volt bulb is known. If you tell me how many amps would the bulb draw from a 3 volt source, I will tell you exactly how many ohms of resistance, and how many watts of power capacity will be required of the resistor.
It is expressed in Volt-Amperes not Watts.