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You can't use one resistor to bring a voltage down, you have to use two in series in a voltage divider configuration, that is two resistors of the same value in serie between positive and negative, then you will have 5V between negative and the point between the resistors, any value can be used depending on the current jou are going to draw, note: you can not use to small a value at least 1K or up, if the value is to small the resistor will get to hot and it can burn out or it can burn your power supply or you can simply use a 7805 voltage regulator chip, it is inexpensive and easy to use, it only have 3 pins 1 = input, 2=GND and 3 is your output, one can get it in many deferent voltages 7803,7805, 7808, 7812 etc. Note: you can even adjust the output voltage between 5V and the RMS value of your power supply, by connecting a pot between GND and the center pin of the regulator, a smoothing cap is needed between GND and the input and one between GND and the output 1 to 10 mf 16V
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What applied voltage will cause a 20 Ω resistor to dissipate 5 Watts?
10V
What does one-quarter W mean for a rated resistor?
It means that the resistor will safely dissipate the heat involved in transporting that much power through, without burning up/out. If you exceed that rating, the resistor will become too hot for its own good.Power is always linked with Voltage and Current, and Current is linked with Voltage and Resistance of the resistor. You will do well to remember the tandem of laws:Power [Watts] = Potential [Volts] * Current [Amperes]andCurrent [Amperes] = Potential [Volts] / Resistance [Ohms]For example, if you have a 100ohm resistor rated at 0.25W, then to satisfy that requirement, a voltage of no more than 5V can be applied to it, because 5V / 100ohm = 0.05A, and 0.05A * 5V = 0.25W.
What does the resistance in an electrical circuit limit?
Current flow. It's also worthy of noting that a resistor doesn't limit-by, it limits-to, and the current is dependent on the voltage. I[A] = U[V] / R[ohm] It's also worth to note, that the power flowing through said resistor with resistance R is I[A] * U[V] for DC circuits - helps to remember this well when picking appropriately-rated resistors for replacement. Example: let's say we have a 20-ohm, 2W resistor. If we place it in a circuit with 5V, we will get 5V / 20ohm = 250mA (0.25A) of current flowing through the resistor. The power the resistor will "see" is 250mA * 5V = 1.25W, so it's safe. But let's now put that same resistor in a 12V circuit. The current flowing will be 12V / 20ohm = 600mA (0.6A), and the power will be 600mA * 12V = 7.2W, so the resistor will burn.
Why do you need 330 ohm resistor for LED?
Generally 330ohm resistors are used to power a typical 3 volt LED if the source voltage is 5v
What is the potential difference neede to send 2a through a 5 ohms resistor?
V=I*R -- Potential (Voltage, V) = Current (Amperage, I) * Resistance (Ohms)2A*5Ohms = 10V
What is the transitive voltage for the voltage input of a CMOS operating from 10V supply?
5V
How do you factorize 10v 12u?
2(5v + 6u)
What will be the sampling frequency if FM equals 5V?
Not less than 10V
What applied voltage will cause a 20 Ω resistor to dissipate 5 Watts?
10V
What voltage will cause a 20 Ω resistor to dissipate 5 Watts?
10V
Why you use level shifter?
in electronics a Level shifter is use when u want take a Bipolar signal and feed it into a unipolar application. Ex. having a signal that swings from -10v to +10v and needing to feed it to a micro-controller that only takes values from 0-5v.
What is the difference between Vrms and Vpeak?
Actually ,Vrms is the root mean square voltage for example, consider voltages 5V,10V,2V So Vrms is the root value of {[(5*5)+(10*10)+(2*2)]/3} And Vpeak is 10V Thanks!!!!!(Zayed)
What does one-quarter W mean for a rated resistor?
It means that the resistor will safely dissipate the heat involved in transporting that much power through, without burning up/out. If you exceed that rating, the resistor will become too hot for its own good.Power is always linked with Voltage and Current, and Current is linked with Voltage and Resistance of the resistor. You will do well to remember the tandem of laws:Power [Watts] = Potential [Volts] * Current [Amperes]andCurrent [Amperes] = Potential [Volts] / Resistance [Ohms]For example, if you have a 100ohm resistor rated at 0.25W, then to satisfy that requirement, a voltage of no more than 5V can be applied to it, because 5V / 100ohm = 0.05A, and 0.05A * 5V = 0.25W.
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.
What does the resistance in an electrical circuit limit?
Current flow. It's also worthy of noting that a resistor doesn't limit-by, it limits-to, and the current is dependent on the voltage. I[A] = U[V] / R[ohm] It's also worth to note, that the power flowing through said resistor with resistance R is I[A] * U[V] for DC circuits - helps to remember this well when picking appropriately-rated resistors for replacement. Example: let's say we have a 20-ohm, 2W resistor. If we place it in a circuit with 5V, we will get 5V / 20ohm = 250mA (0.25A) of current flowing through the resistor. The power the resistor will "see" is 250mA * 5V = 1.25W, so it's safe. But let's now put that same resistor in a 12V circuit. The current flowing will be 12V / 20ohm = 600mA (0.6A), and the power will be 600mA * 12V = 7.2W, so the resistor will burn.
What happens to the current flowing through a metal resistor when the voltage across is increased?
When the voltage is increased across a metal film resistor, the current flow will also increase. Ohm's law states that the current flowing through a resistor is directly proportional to the voltage across that resistor. I = V/R Let us assume an initial voltage drop across a 4.99K ohm metal film resistor is 5V. The current flow through the resistor is calculated to be: I = 5/4990 = 0.001 Amps or 1 mA If that voltage were to say double to 10V: I = 10/4990 = 0.002 Amps or 2 mA Using these values it is also possible to calculate the power dissipated by the resistor. P = I*V = 0.002 * 10 = 0.02 Watts This power calculation determines the minimum physical case size needed for the resistor to function within these conditions. Anything smaller, the resistor will fail.
Why do you need 330 ohm resistor for LED?
Generally 330ohm resistors are used to power a typical 3 volt LED if the source voltage is 5v
