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What do you expect of ohmic resistance as you increase or reduce temperature?
Wiki User
∙ 11y ago
It depends. In general, pure metal conductors increase in resistance as their temperature increases; some alloys (e.g. constantan) are manufactured to maintain an approximately-constant resistance for changes in temperature. Materials such as carbon (and most insulators) exhibit a fall in resistance as their temperatures increase.
Wiki User
∙ 11y ago
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What increase and decrease resistance?
Increase in resistance means that when the resistance of the substance increase by application of some external sources like temperature etc. or when the flow of current through the substance gradually decreases then the resistances increases. Vice versa in case for decrease in resistance.Alternative AnswerResistance is determined by the length, cross-sectional area, and resistivity of a conductor. Resistivity is, in turn, affected by temperature -so temperature indirectly affects resistance.These are the only factors that affect resistance. Voltage and current have no direct effect whatsoever on resistance. Current can affect resistance indirectly if it causes the conductor's temperature to increase.For AC circuits, 'skin effect', due to frequency, causes the current to flow towards the surface of a conductor which acts to reduce the effective cross-sectional area of that conductor. So, frequency can also indirectly affect resistance.
What decreases when current increases?
Power = Current * VoltageP = I*Vtherefore for the same power, when the current decreases, the voltage increasesthis is the concept that is used in transformers for power transmission (increasing the voltage and reducing current to reduce power loss in transmission lines).
What is the working principle of the thermistor?
A thermistor changes it's resistance depending on temperature. Hence Thermal-Resistor. (Thermistor) It is all to do with the crystal structure of the substance the thermistor is made of. Some increase their resistance as temperature rises, called Positive Thermal coefficient, 'PTC'. Others reduce their resistance with increasing temperature, called Negative Thermal Coefficient. 'NTC'. They can be used in a feedback loop of a simple amplifier and switch circuits, to control temperature of a device. They can be calibrated for use in a current loop, to directly measure temperature, like a thermometer. They can be used to stop surges in start up circuits, initially giving a high resistance until things warm up. Or used to apply a large current and then reduce as things warm up. (Like in the old degaussing coils on a colour CRT).
If the resistance in the circuit is increased what will happen to the current and voltage?
* resistance increases voltage. Adding more resistance to a circuit will alter the circuit pathway(s) and that change will force a change in voltage, current or both. Adding resistance will affect circuit voltage and current differently depending on whether that resistance is added in series or parallel. (In the question asked, it was not specified.) For a series circuit with one or more resistors, adding resistance in series will reduce total current and will reduce the voltage drop across each existing resistor. (Less current through a resistor means less voltage drop across it.) Total voltage in the circuit will remain the same. (The rule being that the total applied voltage is said to be dropped or felt across the circuit as a whole.) And the sum of the voltage drops in a series circuit is equal to the applied voltage, of course. If resistance is added in parallel to a circuit with one existing circuit resistor, total current in the circuit will increase, and the voltage across the added resistor will be the same as it for the one existing resistor and will be equal to the applied voltage. (The rule being that if only one resistor is in a circuit, hooking another resistor in parallel will have no effect on the voltage drop across or current flow through that single original resistor.) Hooking another resistor across one resistor in a series circuit that has two or more existing resistors will result in an increase in total current in the circuit, an increase in the voltage drop across the other resistors in the circuit, and a decrease in the voltage drop across the resistor across which the newly added resistor has been connected. The newly added resistor will, of course, have the same voltage drop as the resistor across which it is connected.
What was developed by NASA as a way to keep astronauts from overheating on a spacewalk and is now used by professional and collegiate teams to reduce the number of heat-related injuries?
temperature pill
What would reduce resistance in a copper wire?
Reduce the resistance:-- Use a shorter piece of wire.-- Use thicker wire.-- Cool the wire.Increase the resistance:-- Use a longer piece of wire.-- Use thinner wire.-- File a nick in the piece of wire you have.-- Stretch the wire.-- Heat the wire.
Does pain increase or reduce body temperature?
Increase
How do you reduce the conductivity?
chemical dosing increase, top brine temperature increase, blow down increase, distillate last stage temperature reduce, production increase
How do you reduce conduction?
chemical dosing increase, top brine temperature increase, blow down increase, distillate last stage temperature reduce, production increase
How is electrical resistance decreased?
Ways to reduce electrical resistance: increase the diameter of the conductor, decrease or increase the temperature of conductor (depending on its thermal characteristics), decrease the length of the conductor. A change in the material out of which the conductor is made can decrease resistance, too. And there is the phenomenon of superconductivity. In a simple circuit the resistance can be lowered by adding resistors in parallel. The total circuit resistance will then decrease. You can also reduce resistance by substituting resistors of lower value, or by adjusting a potentiometer, or pot, to a lower value.
How does temperature affect the physical properties of petrol?
An increase in temperature will reduce the density, reduce the viscosity, reduce thermal conductivity, and increase the specific heat capacity. A decrease in temperature will have the opposite affect.
Can Water can decrease a substance resistance to the flow of electricity?
Reduce the temperature of the conductor.
How do you increase the volume of gas?
To increase the volume of a gas * reduce the pressure, or * increase the temperature, or * add more gas
What can be done to alleviate stress?
One is to remove or at least reduce the stressor, and the other is to increase their resistance to it.
How do you increase the pressure of gas?
decreasing the volume available for the gas or increasing its temperature
What increase and decrease resistance?
Increase in resistance means that when the resistance of the substance increase by application of some external sources like temperature etc. or when the flow of current through the substance gradually decreases then the resistances increases. Vice versa in case for decrease in resistance.Alternative AnswerResistance is determined by the length, cross-sectional area, and resistivity of a conductor. Resistivity is, in turn, affected by temperature -so temperature indirectly affects resistance.These are the only factors that affect resistance. Voltage and current have no direct effect whatsoever on resistance. Current can affect resistance indirectly if it causes the conductor's temperature to increase.For AC circuits, 'skin effect', due to frequency, causes the current to flow towards the surface of a conductor which acts to reduce the effective cross-sectional area of that conductor. So, frequency can also indirectly affect resistance.
How do you increase voltage?
You can put less resistance (more load) on the battery with larger wires, but if you exceed a particular current output for a given duration, you will overheat the battery. To safely increase current output, use two batteries connected in parallel.
