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The question needs some clarification / elaboration. The actual power in a resistor depends on how much electric current passes through it. There are plenty of topical (electronics type) web pages that provide a detailed technical explanation. Try Wikipedia. Or browse the technical section of your local library. A more useful question might be - "What value of resistor power rating should I select for a particular application?". So a secondary question would then be - "What is the application?".
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What is the upper control limit of a 1 ohm resistor with a 20 percent tolerance?
A 1 ohm 20% tolerance resistor should not exceed 1.2 ohms actual resistance.
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).
Why you use resistor with variable resistor?
Often we want to easily change a resistor value, so we use a variable resistor. For example, we may want to change the resistor that controls the power sent to a LED, so we can easily make it brighter or dimmer. Often if we use a variable resistor, there is only a very narrow range that is useful. Continuing our example, sometimes we use several LEDs, and we use the variable resistor to set them all to the same brightness. In this case, the resistance range that sets the LED to be twice as bright as the the other LEDs, and the resistance range that sends so much power to the LED that it is permanently destroyed is even less useful. So we add a fixed resistor in series with the variable resistor -- the fixed resistor sets the minimum net resistance, no matter how we turn the knob on the variable resistor. In our example, the addition of the fixed resistor allows us to turn the variable resistor throughout its whole range, and the LED gets brighter and dimmer; without that resistor, a certain range of the knob on the variable resistor would allow so much power to go to the LED that it would be destroyed.
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 an electronic device that limits the amount of current that can flow through it?
A current limiter. Commonly used in well designed power supplies to make the power supply "Fold over" if output current exceeds a safe value. Commonly use a low value resistor in series with the output, and a circuit that senses the voltage across it. Although the above answer describes a circuit to limit current, the device that limits the amount of current flowing through it is a resistor.
What is the upper control limit of a 1 ohm resistor with a 20 percent tolerance?
A 1 ohm 20% tolerance resistor should not exceed 1.2 ohms actual resistance.
What is the function of a cement resistor?
A cement resistor is typically used as a power resistor (a resistor whose power rating is greater than 1 W).
How do you find power generated in a resistor?
The power generated in a resistor is converted into heat. and that can be power which is converted into heat is the product of the voltage across the resistor and, current passing through the resistor. or the product of square of the current and the resistance offered by the resistor.
What is the voltage drop across a 100 W resistor when the electric current flowing through it is measured at 250 mA?
Who can tell? The power rating of a resistor simply tells us the maximum power that resistor is capable of handling; it doesn't tell us anything about the actual power being produced for any given current. So, to find out the voltage drop across that resistor, you will need to find out its resistance, and multiply this value by the current you specify.
What are the basics of how flashlights work?
You need a conductor, power source and a resistor. You need a conductor, power source and a resistor. You need a conductor, power source and a resistor.
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.
To reduce the voltage, I need to change the voltage of 5v to 4.5v, I use a 30 ohm resistor, how many watts of resistor should I use?
To calculate the power rating of a resistor required to drop the voltage from 5V to 4.5V using a 30 ohm resistor, we can use the formula: Power = Voltage Drop x Current The current flowing through the resistor can be calculated using Ohm's law: Current = Voltage Drop / Resistance Substituting the values we get: Current = (5V - 4.5V) / 30 ohms = 0.0167 A (rounded to four significant figures) Now we can calculate the power required: Power = (5V - 4.5V) x 0.0167 A = 0.00835 watts So a resistor with a power rating of at least 0.00835 watts (or 8.35 milliwatts) should be sufficient for this application. However, it is recommended to use a resistor with a slightly higher power rating to ensure that it can handle any temporary power surges or variations in current that may occur. A 0.25 watt resistor should be suitable for this purpose.
At what level will typical resistors burn out?
A typical resistor will burn out when it dissipates power in excess of double its power dissipation rating for an extended period of time. The power dissipated by a resistor is equal to I2R or E2/R, where E = the voltage across the resistor I = the current through the resistor R = the resistance of the resistor
2 resistors unequal value are in parallel. Would the power dissipated by the resistor with larger ohmic value be greater than the power dissipated by the resistor of lesser value?
No, because the power dissipated in a resistor is proportional to the square of the current through the resistor but only directly proportional to the resistance of the resistor (I^2 * R) and the current through the lower value resistor will be higher than the current through the higher value resistor, the lower value resistor will usually dissipate more power.
What physical characteristic determines the power rating of a resistor?
The size of a resistor is a physical characteristic that determines its power rating.
How are current ratings given to a resistor?
Resistors are not usually given 'current ratings' but, rather, 'power ratings' expressed in submultiples of the watt. It is then up to the user to calculate the safe maximum operating current for a particular resistor, by manipulating the equation: P = I2 R.Since a power rating is dependent upon the resistor's ability to dissipate energy by heat transfer, the actual power rating is dependent upon the surface area and, hence, the physical size of the resistor. So you will find that resistors come in a variety of physical sizes for any given resistance value.Unfortunately, power ratings are not indicated through colour codes, etc., so you will have to either specify its power rating when you purchase a resistor, or match your existing resistor against a scale-drawing to determine its power rating.
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..
