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What is name of the resistor whose resistance decrease when light fall on it?
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What is the purpose of the series resistor in your designed ammeter circuit?
You appear to be referring to a 'swamping resistor' which is connected in series with a moving-coil ammeter's moving coil.To minimise any errors due to temperature changes in the resistance of the instrument's moving coil, the coil is connected in series with what is termed a 'swamping resistor' whose resistance is large in comparison with that of the moving coil, and which is manufactured from an alloy with a very lowtemperature coefficient of resistance (i.e. a metal whose resistance is hardly effected by wide variations in temperature).For example, if the resistance of a 1-Ω moving coil increases to, say, 1.1 Ω, when its rated current flows through it, this will introduce a 10% error in the instrument's reading.But by calibrating the instrument with a series swamp resistor of, say, 49 Ω, the overall resistance at rated current will become 50.1 Ω. This will result in an error of just 0.2%.A swamping resistor, then, is an integral part of all moving-coil instruments and, when we refer to an instrument's 'coil resistance', we actually mean the combined resistance of the moving coil itself and its swamping resistor.
How the resistance of conducting material vary with temperature?
Well, there's typically two types of materials-Those with positive temperature coefficient and those with negative temperature coefficient. Positive temperature coefficient are those whose resistance increases as temperature increases. Negative temperature cofficient are those whose resistance decrease when the temperature increase. There are however some alloys such as Manganin& Constantan whose resistance is not affected by temperature
What is role of rheostat?
A rheostat is a resistor with variable resistance.There are many type of rheostat,involved of a rotary-type rheostat and a sliding rheostst.I dunn know much about the rotary-type rheostat but I can tell u how does a sliding rheostat work. A sliding rheostst consists of a coil resistance wire wound on a tube and a sliding contact.The sliding contact be moved on the metal bar.Consider of the length of the resistance wire which let electric current through increases,the reistance would be higher and decrease the elctric current.Thus by moving the sliding contact,we can adjust the size of electric current.It's ofter used as a dimmer or to adjustl the voluime of the radio. If you are interested in the rotary-type rheostat,try to find it by yourself!
What is a resistor in electricity?
Resistor is an eletrical and electronical part whose function is to decrease the value of the voltage in a circuit, consequently reducing the value of the current, which is measured in Amperes.
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).
What is a ballast resistor?
A ballast resistor is an electrical resistor whose resistance varies with the current passing through it, thus maintaining a constant current.
What is the function of ldr?
light dependent resistors are those whose resistivity increases with decrease in the amount of light being exposed on them. The darker the environment, the higher the resistivity.
What is the function of the Light dependent resistor?
The resistance of LDR increases when light is not available (or is limited). And the resistance drops when Light is abundant.This principle can be used in proximity detectors where one or more light source(s) is/are active. When a person / object comes in proximity of the source, the light gets reflected from the object-surface & can now be received by LDR. So due to proximity of the object, resistance of LDR changes - this can be used to trigger different actions like open the door, trigger a motor. Fire an alarm. etc.Resistance of LDR varies according to intensity of incident light over it,It is used in street light to detect day/night and turn on/off the street light automatically
What is the principle of operation of LDR?
Working of light dependent resistor This circuit explains the principle of operation of LDR (light dependence resistor). The circuit has various applications like shadow alarm, automatic night/morning lamp. LDR, an acronym for light dependent resistor is a resistor whose resistance is dependent on light. The resistance of LDR is of the order of Mega Ohms in the absence of light and reduces to a few ohms in presence of light. In this circuit when the light falls on LDR, the resistance of LDR becomes low and the entire voltage drop takes place across the variable resistance VR1 (10K). As a result the base of transistor (T1) gets high input and it gets biased thereby glowing the LED. When no light falls on LDR, the resistance of LDR becomes high so almost entire voltage drop takes place across it and the base of transistor is at low potential. So transistor does not gets biased nor it becomes conducting, hence switching off the LED. The sensitivity of the circuit can be adjusted by varying the preset VR1. LDR, an acronym for light dependent resistor is a resistor whose resistance is dependent on light. The resistance of LDR is of the order of Mega Ohms in the absence of light and reduces to a few ohms in presence of light. In this circuit when the light falls on LDR, the resistance of LDR becomes low and the entire voltage drop takes place across the variable resistance VR1 (10K). As a result the base of transistor (T1) gets high input and it gets biased thereby glowing the LED. When no light falls on LDR, the resistance of LDR becomes high so almost entire voltage drop takes place across it and the base of transistor is at low potential. So transistor does not gets biased nor it becomes conducting, hence switching off the LED. The sensitivity of the circuit can be adjusted by varying the preset VR1.
What is the purpose of the series resistor in your designed ammeter circuit?
You appear to be referring to a 'swamping resistor' which is connected in series with a moving-coil ammeter's moving coil.To minimise any errors due to temperature changes in the resistance of the instrument's moving coil, the coil is connected in series with what is termed a 'swamping resistor' whose resistance is large in comparison with that of the moving coil, and which is manufactured from an alloy with a very lowtemperature coefficient of resistance (i.e. a metal whose resistance is hardly effected by wide variations in temperature).For example, if the resistance of a 1-Ω moving coil increases to, say, 1.1 Ω, when its rated current flows through it, this will introduce a 10% error in the instrument's reading.But by calibrating the instrument with a series swamp resistor of, say, 49 Ω, the overall resistance at rated current will become 50.1 Ω. This will result in an error of just 0.2%.A swamping resistor, then, is an integral part of all moving-coil instruments and, when we refer to an instrument's 'coil resistance', we actually mean the combined resistance of the moving coil itself and its swamping resistor.
How the resistance of conducting material vary with temperature?
Well, there's typically two types of materials-Those with positive temperature coefficient and those with negative temperature coefficient. Positive temperature coefficient are those whose resistance increases as temperature increases. Negative temperature cofficient are those whose resistance decrease when the temperature increase. There are however some alloys such as Manganin& Constantan whose resistance is not affected by temperature
What is role of rheostat?
A rheostat is a resistor with variable resistance.There are many type of rheostat,involved of a rotary-type rheostat and a sliding rheostst.I dunn know much about the rotary-type rheostat but I can tell u how does a sliding rheostat work. A sliding rheostst consists of a coil resistance wire wound on a tube and a sliding contact.The sliding contact be moved on the metal bar.Consider of the length of the resistance wire which let electric current through increases,the reistance would be higher and decrease the elctric current.Thus by moving the sliding contact,we can adjust the size of electric current.It's ofter used as a dimmer or to adjustl the voluime of the radio. If you are interested in the rotary-type rheostat,try to find it by yourself!
What is a resistor in electricity?
Resistor is an eletrical and electronical part whose function is to decrease the value of the voltage in a circuit, consequently reducing the value of the current, which is measured in Amperes.
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).
What is a barretter?
It is a rifle made by the American Barrett Firearms Company. They are most famous for their M107 50 caliber rifle.
What is photo conductors?
A photoconductor is something whose resistance decreases when it's exposure to light increases. As for Photography, the only link I know of is that they are used in light meters.
Explain the working of LDR and mention any five applications of LDR in detail?
A photoresistor, light dependent resistor (LDR) or cadmium sulfide (CdS) cell is a resistor whose resistancedecreases with increasing incident light intensity. It can also be referred to as a photoconductor.Applications:camera light meters, street lights, clock radios, alarms, and outdoor clocks
