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The formula you are looking for is W = I x E.
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∙ 13y ago
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Can you connect a 20 watt lamp directly to a 12 volt dry cell?
If it's a 12V lamp - sure. But, depending on the battery and the complexity of the installation it might be wise to put a fuse in the circuit too, right up by the battery.
When you turn on a lamp are you opening or closing a circuit?
Your closing the circuit!
If you are using a multimeter as an ohmmeter and you get a reading of maximum resistance what does that tell you about the circuit you are measuring?
Did you mean "maximum RESISTANCE" or "maximum VALUE"? If the former, then, you have a ZERO reading, meaning there is high resistance, and no electrical connectivity. If the latter, you have a ONE (or 100%) reading, meaning there is NO resistance, or absolute electrical connectivity. As an analogy, if you turn on a plugged-in, working, lamp, then it has NO resistance, such that power flows easily through the cord; if it didn't turn on, then there IS resistance, such that no power flows, possibly due to broken wire, bad switch, burned-out bulb, or blown fuse.
What is the resistance value for LED bulb in 12v DC circut?
48 ohms
The number of ohms in a circuit is a measure of the?
The electrical resistance of the circuit
If a 12 volt parallel circuit has 4 lamps and each lamp consumes 1 amp what is the resistance of each lamp?
Assuming you mean the 4 lamps are in parallel with each other: the total voltage drop across each lamp is still 12V. As we know that V= IR (Voltage = I Current times Resistance) 12 = 1 x R so Resistance = 12 Ohms for each lamp.
If each lamp is rated 12v 24w what is the current consumed by each lamp?
2 amperes in a parallel circuit. I = W/V. It is true provided that 12v are delivered to the lamps in parallel circuit. In a series circuit, the voltage is divided among the lamps so that the total current is probably 2 amperes for all lamps.
I need to draw a circuit diagram to show this but I have no idea how do you find the resistance of a lamp in a circuit?
If you have a lamp, you can assume that the resistance of the lamp when it is under power will follow the ohms law. BUT, one thing you must remember is, when a lamp is under load, it is glowing HOT. When metal is HOT, the molculoes of the meals are in much more active state. When this happens, the resistance will increase. Conversely, when the lamp is NOT on ON state, the filaments are cold. Moleculoes in the filaments are not as active. Thus, the resistance is lower. There is almost 10 to 1 difference in resistance from hot to cold. Taking out a multimeter and measuring the resistance of the lamp will not help you determine the resistance of the lamp when it is actually under load (with voltage applied) Really, the only thing you can do is to measure the voltage, measure the current, then arrive at the resistance mathmatically.
What happens to the ammeter reading when a lamp is added to a circuit which contains two cells and a lamp in series?
Assuming the new lamp is in series, the ammeter reading falls because the total resistance has increased. By how much depends on how the lamp resistance depends on voltage. If the lamp is added in parallel to the first, then the ammeter reading doubles.
When a 12 V battery is connected across an unknown resister there is a current of 2.5 mA in the circuit find the value of the resistance of the resistor?
Resistance = voltage / current = 12V / 2.5mA = 12V / (2.5 x 10-3 A) = 4.8 x 103 ohm
What will be the amps of a 12v 2amp circuit if there is a 12ohm resistor on it?
The formula you are looking for is I = E/R. Amps = Volts/Resistance. If you say it is normally a 2 Amp circuit, it normally draws 2 amps. Therefore the original resistance offered to the 12v battery is 2/12 = 6 Ohms. If you then connect a 12 Ohm resistor in series, they are added, so R = 18 Ohms. Now if you put 12v across this circuit it will draw 12/18 = 0.66 Amps. Or If you just put a 12 Ohm resistor across the 12v supply it will draw 1 Amp. If the circuit is protected by a 2 Amp fuse, it will not blow, but the resistor will get hot.
Can you connect a 20 watt lamp directly to a 12 volt dry cell?
If it's a 12V lamp - sure. But, depending on the battery and the complexity of the installation it might be wise to put a fuse in the circuit too, right up by the battery.
How does a 6volt relay circuit works?
The same as a 12V relay circuit, except it only needs 6V instead of 12V.
To run 12v dc things in a car the battery outputs 12v regularly but it can go as high as 14.4 when the engine is running I need a circuit to regulate this at say 12v 10 amps to prevent over voltage?
the alternator is what puts out the 14.4 volts. if you wish to figure out the circuit use the formula A*R=V so you take the voltage 12 divide by the amp 12 and you get 1.2 as the resistance. so in your circuit, the max allowable load is 1.2 ohms.
What would happen to circuit if there was no resistance?
a circuit with no resistance or zero resistance can be considered as open circuit in which the current is zero. without resistance the circuit just becomes open ()
Does increasing the resistance increase the electric current?
If the current through a pure metallic conductor causes the temperature of that conductor to rise, then its resistance will increase. A practical example of this is an electric lamp. The cold resistance of a lamp is very much lower than the hot resistance.
What power is supplies to a lamp that is operated by a battery moving a 12V difference of potential across it's terminals when the current through the lamp is 2A?
The Formula is: P=IV =(2A)(12V) =24W
