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The ability of any component part to radiate heat depends partly on the materials it is made from and mainly on its surface area. So, as large-sized resistors have a much bigger surface area than small ones, the power rating of a resistor is made according to the power (Watts) it has been designed to dissipate safely without overheating.
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When resistors are connected in series then what happens to the watt?
Resistors are rated in wattage so the lowest wattage rating will be the wattage of the series circuit. It will be able to handle that power any more and the lowest wattage resistor could be damaged and fail.Another AnswerWhen two or more resistors are connected in series, the resistor with the lowest resistance will operate at the highest power. If the power developed by a resistor exceeds its rated power, then the resistor may burn out.
When all resistors are equal value the total resistance is equal?
This depends on whether your resistors are in serial or parallel. If they are in serial, the value of the resistors just adds up, so : Val(total) = val(single) x n(umber of resistors) If they are in parallel, each added resistor lowers the total value, while the power rating rises : Val(t) = 1/ ( val(s) x n)
Do additional resistors affect power?
Of course. Additional resistors change total resistance, which changes current, which affects power.
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.
What is a resistor bank?
In simple way resistor bank contains number of resistors in series or parallel combination. They are connected in parallel to decrease the resistance and increase current rating and power dissipation.And they are connected in series to increase resistance and power dissipation.
How does temperature affect power rating of carbon resistors?
Its normal power rating is at room temperature. For a temperature of 75 degrees, halve the rating.
What are the types of resistor?
There are many types of Resistors , which can be classified in many ways. The fundamental classification is based on the Power Handling Rating , which breaks up into Power Resistors & Low power resistors. Power Resistors can handle large Powers & Currents. These are generally made of High Resistance alloys like Nichrome , which are used in heaters , toasters etc. Some types of small power resistors are also used in electronic circuits which handle large currents like in power supplies etc. Infact the incandescent lamp is a special form of power resistor. Low power resistors are usually used in electronic circuitry , which again have different power capacity ratings usually less than 1watt to small surface mounted devices which are rated for few tenths of milliwatts. Another important classification is based on the stability of the resistor material & hence its ohmic values. Such resistors are used for precision applications like measuring circuits , meters etc. Then there are specialised forms of clasification depending on application e.g Positive & Negative Temeprature coefficient resistors ( Thermistors ) are used for temperature sensing , Voltage Dependent resistors are used in protection circuitry, High Voltage resistors are used where requires for high voltage ( kilovolts ) electronic circuitry like X Ray , Laser & Electrostatic Power supplies.
When resistors are connected in series then what happens to the watt?
Resistors are rated in wattage so the lowest wattage rating will be the wattage of the series circuit. It will be able to handle that power any more and the lowest wattage resistor could be damaged and fail.Another AnswerWhen two or more resistors are connected in series, the resistor with the lowest resistance will operate at the highest power. If the power developed by a resistor exceeds its rated power, then the resistor may burn out.
If you are only given 1 kilo ohms resistors with 0.5 watt power rating how can you construct a resistive load of 1 kilo ohms with 1 watt power rating?
Well...you can't. Not a load with an exact 1 watt power rating. But if you can live with a 2-watt power rating (in a circuit that would be yes--it's called derating and you do it for added life, or because you've already got the parts) you'd connect two resistors in series and set that aside, connect two more resistors in series, then connect the two series networks in parallel. Each series network is rated at 2 kilohms; paralleling the two networks brings you back down to 1 kilohm.
Why are resistors called resistors?
Resistors have resisting power(resists the electric power).Due to having the resistive property, the name resistor is given to such electrical device.
Why do resistors sometimes burn out when they run close to their power rating?
They're just "things" ... the power ratings are only approximations AND power fluctuations also occur - so your 5 watt load may become 6. (or 10)
When all resistors are equal value the total resistance is equal?
This depends on whether your resistors are in serial or parallel. If they are in serial, the value of the resistors just adds up, so : Val(total) = val(single) x n(umber of resistors) If they are in parallel, each added resistor lowers the total value, while the power rating rises : Val(t) = 1/ ( val(s) x n)
Do additional resistors affect power?
Of course. Additional resistors change total resistance, which changes current, which affects power.
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.
What is a resistor bank?
In simple way resistor bank contains number of resistors in series or parallel combination. They are connected in parallel to decrease the resistance and increase current rating and power dissipation.And they are connected in series to increase resistance and power dissipation.
How sensitive is 22k resistor?
"Sensitivity" is not a word normally applied to resistors. Characteristics of resistors include "resistance", "tolerance", "power rating", and "temperature coefficient". "Inductance" and "capacitance" are also used in describing certain critical performance resistors. A 22 KOhm resistor will require 22 v of voltage to induce a current of 1 ma. This is Ohm's Law: voltage = current times resistance.
How much power does a string of 6 4.5v 40ma led's consume?
The total power of a series of resistors is equal to the sum of the power dissipated by individual resistors. In this case, each resistor consumes 4.5v*.04amps which is equivalent to 1.08 watts. Since there are 6 resistors, 6.48 watts of power are consumed.
