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What is the power dissipated by a 10 ohm resistor with 20 volts supply?
Wiki User
∙ 8y ago
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 Amperes
Watts is Voltage times Amperes
Alternative Answer
Divide the square of the voltage by the resistance.
Wiki User
∙ 8y ago
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What is the voltage drop across a 12 ohm resistor with a source of 24 volts?
If there's nothing else between the ends of the resistor and the power supply, then the voltage across the resistor is 24 volts, and the current through it is 2 amperes.
What is the power dissipated in the Ohm resistor?
Power dissipated is always Volts times Amps. W= V*I because of ohm's law, V=I*R, you can substitute either the voltage or amperage with the other value; W= V^2/R or W= I^2*R.
Is the heat loss and current of a resistor affected by being in a parallel circuit or can you just calculate it the same as in series?
The heat generated by any particular resistor depends (at least electrically) solely on the power it dissipates. Power dissipation in a resistor is equal to current squared times resistance, and the current through the resistor is equal to the voltage across it divided by the resistance. If we take a 10 ohm resistor ('your resistor') and put it in a series circuit such that there is 10 volts across your resistor, the current through it will be 1 ampere (10/10=1). the power dissipated will be 10 watts (1^2 * 10=10). If we put your resistor in a parallel circuit that also puts 10 volts across it, then the current and power will be the same. Your resistor does not know or care where the voltage came from. From this point of view, once you get down to the voltage across the resistor, it does not matter what type of circuit it is in. On the other hand, for any given power supply voltage, then the type of circuit and the value of external components certainly does affect the terminal voltage and thus the current through as well as the power dissipated by the resistor. In a parallel circuit, the voltage across your resistor remains basically the same no matter what resistance you put in parallel with it (unless you overload the power supply or the power supply has high internal resistance). In this case, the voltage across the resistor is the same as the power supply, current is I=E/R, R being that resistor only, and power is P=I^2 * R. In a series circuit the current through the resistors is I=E/R, R being the total resistance (including the other resistor(s)). The power dissipation in your resistor will then be P=I^2 * R, I being the series current we just calculated, and R being your resistor only. Since the other resistors affect the current, and since the current is the same no matter where you measure in a series circuit, then the voltage across your resistor and thus the power dissipation will be affected. The voltage across your resistor will be E=I*R, I being the series current we just calculated, and R being your resistor only. So, while the calculation for power dissipated in a particular resistor does not change relative to what type of circuit it is in, the calculation to arrive at the voltage across the resistor and/or the current through it (which you will then need to calculate power) does. Keep in mind there are other mechanical parameters that influence the actual case temperature of the resistor. Physical size of the case, composition, and airflow velocity, if any, will alter the case-to-ambient thermal conductivity. Ambient temperature will also be a factor in the final temperature.
Determine the power dissipated if the voltage supplied to a circuit is 12V and the current measured is 3A?
The power dissipated by a circuit with a voltage of 12V and a current of 3A is 36W. Watts is Volts times Amps.
How do you reduce 48 volts dc to 12 volts dc with resistors?
Yes. You can use a voltage divider. Say, for instance, one 1KOhm resistor in series with a 3KOhm resistor. Connect the 3k resistor to the 48 volts and connect the 1k resistor to ground. The 1k resistor will have 12 volts acress it. These resistors need to be at least 1 watt each as they are going to dissipate 0.576 watts and get warm. Now, if you attempt to pull power from the 1k resistor, note that regulation will be poor because the impedance of the load will go in parallel with the 1k resistor and change its value.
Voltage drop of 15 Volts across 2.7 killo ohm resistor?
You just stated that the voltage across the resistor is 15 volts, so that's your answer ! If the resistor is connected to a 15-V battery or to the output of a 15-V power supply, then a meter across the resistor is also across the power supply, and reads 15 volts. The current through the resistor is (V/R) = (15/2700) = 5.56 mA. The power dissipated by the resistor (and delivered by the battery) is (V2/R) = (225/2700) = 0.083 watt.
What is the result in voltage of applying a 2.7 ohm resistor to a 12 volt DC circuit?
The question has just stated clearly that the applied voltage is 12 volts DC.Provided that the power supply is capable of maintaining its output voltage while supplying some current ... i.e. that the effective internal resistance of the power supply is small ... and that the 2.7 ohm resistor is the only external element connected to the power supply's output, the voltage across the resistor is exactly 12 volts DC.The current through the resistor ... supplied by the 12 volt DC supply ... is 12/2.7 = 4.44 Amperes (rounded).The power dissipated by the resistor ... supplied by the DC supply ... is 122 / 2.7 = 53.23 watts !
What is the current running through a resistor of 9 ohms with volts of 90?
I = E / RIf the voltage across the resistor is 90 volts, and the resistance of the resistoris 9 ohms, then the current through the resistor is90/9 = 10 Amperes.Don't try this at home!The power dissipated by the resistor is E2/R = (90)2/9 = 900 watts. That's comparable to the power (heat) dissipated by a small toaster. A common composition resistor will get hot and possibly explode if it's asked to dissipate that kind of power.
How much power will be dissipated by a 9 ohm resistor if 9 volts are applied across it?
P = (E2)/R = 81/9 = 9 watts
What is the power dissipated by a resistor that has 5 amps flowing through it with 120 volts applied?
The power in a resistor (in watts) is simply the product of the current (in amperes) times the voltage (in volts).The power in a resistor (in watts) is simply the product of the current (in amperes) times the voltage (in volts).The power in a resistor (in watts) is simply the product of the current (in amperes) times the voltage (in volts).The power in a resistor (in watts) is simply the product of the current (in amperes) times the voltage (in volts).
What is the power dissipated in the resistor?
Power dissipated is always Volts times Amps. W= V*I because of ohm's law, V=I*R, you can substitute either the voltage or amperage with the other value; W= V^2/R or W= I^2*R.
What is the voltage drop across a 12 ohm resistor with a source of 24 volts?
If there's nothing else between the ends of the resistor and the power supply, then the voltage across the resistor is 24 volts, and the current through it is 2 amperes.
What is the power dissipated in the Ohm resistor?
Power dissipated is always Volts times Amps. W= V*I because of ohm's law, V=I*R, you can substitute either the voltage or amperage with the other value; W= V^2/R or W= I^2*R.
How do you determine the amperage given the voltage and power dissipated?
Like Ohm's Law, the formula for calculating power is a simple product of two quantities. It is given by the formula P = VI, where V is the voltage in volts and I is the current in amperes (or simply amps). So, if you know the value of any two of the quantities, you can easily calculate the third with simple arithmetic. For example, if the current flowing through a resistor is two amps and the voltage drop across that resistor is five volts, the power dissipated by the resistor is, P = VI = 5 volts * 2 amps = 10 watts. If you are given the power and the voltage, you can easily find the current. For example, if you are told that the voltage drop across a resistor is five volts and is dissipating 10 watts, the current through the resistor is 10 watts/5 volts = 2 amps.
Calculate the resistor in a circuit having 12V source voltage and power dissipation of 10 W?
0.069444444444444444444444444444444444 ohms. P/E^2=R. P = power in watts. E = electricity in volts. R = resistance in ohms.
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 is the Power dissipated from a 0.5A current through a 5ohm resistor?
The current I = 0.18257 amperes. Scroll down to related links and look at "Electrical voltage V, amperage I, resistivity R, impedance Z, wattage P".
