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What size resistor is needed to drop 12 volt dc to 3 volt what is the formula?
JuliusEscuadro
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.
Wiki User
∙ 15y ago
Wiki User
∙ 10y agoThe voltage drop is equal to the current in amps times the ohms. For a constant-current load just divide the voltage-drop by the current to find the necessary resistance in ohms. For a varible load a simple voltage regulator should be used.
Wiki User
∙ 11y agocannot determine without other information not given.
using a voltage regulator would be the better way to go
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What size resistor needed to drop 3 volts dc to 2.5 volts dc?
You will need to take the resistance of the load into account if you are going to design a voltage divider. The resistance of the load can completely change the voltage ratio of a voltage divider if not factored into the calculation. you can measure or read R(load), then R(needed) = 0.8 R(load)
Is it true that the higher a resistance value the higher the voltage drop?
Greater value resistor will absorb more voltage than smaller value. The more voltage absorb with same value current flow, the larger body mass resistor will require. Body size depends on type of resistor (material resistor is made of).
What is the formula of 2 phase power?
The formula which are needed for making of a single phase transformeri.e o/p voltage,watt,current,turn,core size,coil number,bobin size etc
When resistors are connected in series in a circuit. what are the relationships between the voltage drops across the resistor and the currents through the resistors?
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How do you calculate the voltage drop for 238 KW 3 phase 415 V and length of circuit is 20 meters?
You need also to know the resistance of the cable. First you establish what the current of the load is. Then from that you calculate the wire size. From a wire size chart you find the wire resistance. Then use the formula I (squared) x R.
What size resistor is needed to drop 24 volts dc to 12volts dc?
Its dependent what will by rated power of the device (current).
What size resistor is needed to drop from 5vdc to 3vdc?
use Ohm's law: to drop 2 volts, V = I x R 2 = current x resistance resistance = 2 / current. So you need to know the current
What size resistor is needed to drop 14 volts dc to 12 volts dc?
This question cannot be answered because you did not specify the current.
What is the volt drop across a 10k resistor with a 5 volt supply?
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.
What size resistor to drop 12 vdc to 2vdc?
it is better to use zener diodes or transformators in order to drop 12 vdc to 2 vdc. If you do it with resistor you will waste you power. Voltage formula for resistors in series V1+V2+........+Vn=Vtotal, so 2Vdc+i.R=12Vdc. Determine the current for you supplier and calculate the value of resistance.
What size resistor needed to drop 3 volts dc to 2.5 volts dc?
You will need to take the resistance of the load into account if you are going to design a voltage divider. The resistance of the load can completely change the voltage ratio of a voltage divider if not factored into the calculation. you can measure or read R(load), then R(needed) = 0.8 R(load)
What size resistor to drop 9 dc to 3 dc at 1 amp?
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What size resistor needed to fool o2 sensor?
It doesn't work that way. An oxygen sensor can not be bypassed.
What size resistor in parallel to reduce from 120 volts to 100 volts?
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What is the relation between the size of the resistor and its value?
There is no relation between the resistor's ohms value and its size. The power of the resistor can be seen by its size. If the power is too small, the resistor can be destroyed.
Is it true that the higher a resistance value the higher the voltage drop?
Greater value resistor will absorb more voltage than smaller value. The more voltage absorb with same value current flow, the larger body mass resistor will require. Body size depends on type of resistor (material resistor is made of).
Can you measure the physical size of a resistor to determine its wattage?
there might be ways to get the power rating by measuring the size of the resistor. but as the physical size of the resistor increases, its power rating also increases..
