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Why the induced EMF is negative when the voltage in the first coil increasing?
Wiki User
∙ 10y ago
It's an increasing current, not voltage, that induces an e.m.f. into a coil. The reason that the induced e.m.f. opposes the increasing current is all to do with the Law of the Conservation of Energy.
Wiki User
∙ 10y ago
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What rule should you use in order to determine the direction of induced EMF in a coil?
The direction of an induced voltage is such that it always acts to oppose any change of current which causes it.So, for example, during the first quarter-cycle of a sine wave, when the current is increasing, the induced voltage acts oppose that change (increase) -in other words, it acts in the opposite direction to that current. During the second quarter-cycle of a sine wave, when the current is decreasing, the induced voltage again acts opposethat decrease that change (decrease) -in other words, it acts in the same direction to that current -trying to sustain that current.
When can voltage be induced but not current?
"Induced" is the verb you are looking for. A current is induced in the secondary circuit by the current in the first changing, provided both conductors are close enough for the driving current's electro-magnetic field to enclose the second conductor. Note that word "changing". Direct current produces a field but that remains constant and does not induce a secondary current, as a.c. does.
How do you find the voltage at a point in a circuit with respect to a negative voltage?
First of all, 'voltage' means potential difference -and you cannot have a potential difference 'at a point'. Similarly, you cannot have a 'negative' potential difference, so it doesn't make sense to talk about a 'negative voltage'.Your question, therefore, should read: 'How do you find the potential at a point in a circuit with respect to a negative potential?'The answer is that you simply connect a voltmeter between the two points. The reading will give you the value of the potential. If it reads upscale, then it'll be positive; if it reads downscale, then it will be negative (i.e. even more negative tan the reference potential).
Which charge is voltage carried by in an electrical circuit?
Well, first of all, voltage is not carried. Voltage is the 'pressure' between the ends of a circuit that makes charges want to flow. The charge carriers that actually do the physical flowing are the electrons, with their negative charges. When they flow, we say that there is 'current' in the conductor.
When slip ring get negative charge in ac generator?
you apply dc voltage to slip rings in synchronous generators polarity will make no difference ( other than when it is first applied )
What rule should you use in order to determine the direction of induced EMF in a coil?
The direction of an induced voltage is such that it always acts to oppose any change of current which causes it.So, for example, during the first quarter-cycle of a sine wave, when the current is increasing, the induced voltage acts oppose that change (increase) -in other words, it acts in the opposite direction to that current. During the second quarter-cycle of a sine wave, when the current is decreasing, the induced voltage again acts opposethat decrease that change (decrease) -in other words, it acts in the same direction to that current -trying to sustain that current.
For voltage to be induced from one stationary wire to another one wire must have a n what type of current flow?
Intermittent. Faraday's law tells us that voltage can only be induced in a second coil when the current in the first coil changes
When measuring voltage how should test probes be connected?
First connect the positive terminal of the voltage line to positive terminal of multimeter and negative to negative terminal of multimeter. Select voltage in multimeter and measure the voltage
When can voltage be induced but not current?
"Induced" is the verb you are looking for. A current is induced in the secondary circuit by the current in the first changing, provided both conductors are close enough for the driving current's electro-magnetic field to enclose the second conductor. Note that word "changing". Direct current produces a field but that remains constant and does not induce a secondary current, as a.c. does.
Is it okay to remove the positive terminal ahead of the negative terminal why?
It is recommended to remove the negative first. It causes less of a voltage spike if the ground is removed first.
Why are condenser adjustments generally preferred over the use of the voltage control?
"When increasing the lighting, be sure to open up the diaphragm first instead of increasing the voltage on your lamp; the reason is that lamp life is greatly extended when used at low voltage." Source: Benson Microbiological Applications 11th edition pg.7
Why are condensers adjustments generally preferred over the use of the voltage control?
"When increasing the lighting, be sure to open up the diaphragm first instead of increasing the voltage on your lamp; the reason is that lamp life is greatly extended when used at low voltage." Source: Benson Microbiological Applications 11th edition pg.7
What changes the flow of electrons in an alternating current?
first of all the voltage doesn't change what changes is the current direction the way they do it is by using magnet . electrons tend to escape from the magnetic field . you can find on you tube how a motor works for better idea.
How do you find the voltage at a point in a circuit with respect to a negative voltage?
First of all, 'voltage' means potential difference -and you cannot have a potential difference 'at a point'. Similarly, you cannot have a 'negative' potential difference, so it doesn't make sense to talk about a 'negative voltage'.Your question, therefore, should read: 'How do you find the potential at a point in a circuit with respect to a negative potential?'The answer is that you simply connect a voltmeter between the two points. The reading will give you the value of the potential. If it reads upscale, then it'll be positive; if it reads downscale, then it will be negative (i.e. even more negative tan the reference potential).
Why there is an induce current in a coil when a coil is compressed in a magnetic field?
compressing a coil in a magnetic field means that there is a relative movement of the the said coil existing in a magnetic field, hence current will be induced. induction law.Another Answer'Current' is not induced into a coil. It's voltagethat's induced; if the coil forms a closed loop, then current will flow; if there is no closed loop, then no current will flow.The induced voltage results from either a change in current through the coil, or from the relative movement between the coil and an external magnetic field.
How do use a volt meter?
1. Attach the positive input terminal lead to the positive end of the circuit (or whatever you want to measure the voltage of). 2. Attach the negative input terminal lead to the negative end of the circuit (or whatever you want to measure the voltage of). The voltmeter will turn itself on and measure the difference between the voltage at the first point and the voltage at the second point, telling you how much voltage is traveling between the two points so that is how to use it effectivelly.
Why is a positive times a negative always a negative?
It might be clearer if you think of it this way: Multiplication is repeated addition. 2 x 3 is the same as 3 + 3. They both equal 6. 2 x -3 is the same as -3 + -3. They both equal -6. In the first case, you are increasing the amount of positive things. The answer will be positive. In the second case, you are increasing the amount of negative things. The answer will be negative.
