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What else can I help you with?
What causes resistance to increase or decrease?
Voltage, if voltage is increased resistance in the circuit increasesAnswerResistance 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 is the formula for resistivity?
Resistance (Ohms) = Voltage (v) / Current (I)
What will happen to resistance If amperage goes down and voltage remains the same?
The correct term is 'current', not 'amperage'. The answer is that nothing will happen to the resistance. Having said that, changing the resistance will cause current to change for a fixed value of voltage.Resistance is determined by the length, cross-sectional area, and resistivity of a material. Resistivity is affected by temperature, so resistance is also therefore indirectly affected by temperature. Only by changing one of these variables will the resistance change.Since the ratio of voltage to current will tell us what the resistance of a circuit happens to be (it's not affected by that ratio) for a particular ratio, the ratio will increase (as per your question) if the resistance increases. But it's not the ratio that's affecting resistance, its the resistance affecting the ratio!
What is charging current in transmission lines?
Any two conductors separated by an insulating medium constitutes a condenser or capacitor.In case of overhead transmission lines, two conductors form the two plates of the capacitor and the air between the conductors behaves as dielectric medium. Thus an overhead transmission line can be assumed to have capacitance between the conductors throughout the length of the line. The capacitance is uniformly distributed over the length of the line and may be considered as uniform series of condensers connected between the conductors.When an alternating voltage is applied across the transmission line it draws the leading current even when supplying no load. This leading current will be in quadrature with the applied voltage and is termed as charging current. It must be noted that charging current is due to the capacitive effect between the conductors of the line and does not depend on the load. The strength of the charging currents depends on the voltage of transmission, the capacitance of the line and frequency of the ac supply. It is given by the expressionSignificance of Charging currents:Capacitance effect (responsible for charging currents) of the short transmission lines are negligible. However they are significant in medium and long distance transmission lines.In long distance transmission lines, during light loaded conditions receiving end voltage will be higher than sending end voltage. This is because of the charging currents and capacitive effect of the line
What is voltage drop per foot?
Voltage drop is caused by resistance. From the equation V=IR the voltage across that resistance can be calculated. For a uniform conductor the resistance is linear with the length R=kx where k is in ohms per foot. For a given current, the voltage drop V=Ikx so the voltage drop per foot is Ik. Voltage drop per foot can be measured, allowing a calculation of voltage drop for very long lengths of conductor such as power transmission lines. This is a reasonable approximation as long as the total voltage drop in transmission is small relative to the supply voltage. If the voltage drop is large, the current will be limited by the total resistance. This implies that long distance transmission lines should be high voltage, because 1 megawatt at 10,000 volts requires 100 amps, while at 100,000 volts it only requires 10 amps. The voltage drop per foot for the same conductor would be 10 times as large at 10 times the current, and the power loss (I*IR) would be 100 times as large. For alternating current, inductance can be a factor; this implies that relatively low frequency would be preferred.
What is the effect of changig length or mass of pendulum on value of g?
Changing the length will increase its period. Changing the mass will have no effect.
How does arc length affect voltage?
The longer you strech the arc, the smaller the voltage. Current rises though.
Relationship between the length of wire and its electric current?
The relationship between the length of a wire and its electric current is inversely proportional - as the length of the wire increases, the electric current decreases. This is due to increased resistance in the longer wire, which limits the flow of current. Thus, longer wires have higher resistance and lower current flow compared to shorter wires.
What are some testable questions involving electric currents?
How does the length of a wire affect its resistance in an electric circuit? What is the relationship between the voltage and current in a resistor? How does the number of coils in an electromagnet affect its magnetic strength? What is the effect of changing the type of material in a circuit (e.g. copper vs. aluminum) on the flow of electric current?
What is the relationship between wire size length of run and voltage drop?
The wire resistance is proportional to the length of wire divided by its cross-section area. The voltage drop is proportional to the resistance times the current.
What will happen to the current if double the length of the wire?
If you double the length of the wire while keeping the resistance constant, the current will halve because resistance is directly proportional to the length of the wire. This is described by Ohm's law (V = I * R), where V is voltage, I is current, and R is resistance.
How can you select the current values for welding?
The amount of current (amps) is controlled by the user. It's done with a variable resistor. Another thing to note is whether you are welding constant current or constant voltage. If you are welding constant current, the voltage will vary and a set Amp measure will remain constant. With constant voltage, the current will vary and that's determined by the resistance. Constant voltage should be an easier set up. I'm not 100% sure but most stick welding is constant current, which is why increasing the arc length produces more heat, because more arc length should increase the resistance, which would cause the welding machine to increase voltage to keep the current constant.
What is voltage harmonic?
In AC current, its a quality measurement of voltage. If voltage is harmonious or "clean" you will see an equal wave length on both sides of your baseline. You can test and see this using an electrical scope.
What does power divided by speed equal?
Ohm so correctly said: Voltage divided by current equals resistance. Voltage divided by current will tell you the value of a circuit's resistance. But resistance is not affected by either voltage or current. It is determined by the length, cross-sectional area, and resistivity (type of conducting material) of the conductor. Resistivity is, in turn, affected by temperature. So voltage divided by current tells you what the resistance happens to be - changes in voltage or current do not affect resistance.
What is the physical length of a voltage waveform?
Voltage does not have a waveform. The waveform is based upon the frequency of the voltage or current. A battery (any voltage) does not waveform, however the voltage coming into your house (US) has a frequency of 60 Hz. The length of the 60 hz waveformLength (in centimeters) = (3 x (10 ** 10))/ Frequency in hz =500 000 000 cm
Does increasing the voltage across a resistor increase the electric current through the resistor?
Resistance is not affected by either voltage or current. It is determined only by the cross-sectional area, length, and resistivity of the material. As resistivity is affected by temperature, resistance is indirectly affected by temperature.In the so-called 'Ohm's Law' equation, resistance is a constant. So, if you increase voltage, the resistance remains constant, and the current would increase in proportional to the voltage.
What is the value of a resistor when current and voltage are both zero?
The value can be anything.As long as the resistance is not zero, if the voltage across the resistor is zero the current through the resistor will also be zero.The relevant equations is...Voltage = Resistance x CurrentIn the special case of superconductivity, the resistance is zero and you can have a current even if the voltage is zero.AnswerResistance is affected by the length of a material, its cross-sectional area, and its resistivity (which, in turn, is affected by temperature). The resistance of a resistor, therefore, is not affected by either voltage or current.
