Why voltmeter is always connected in parallel combination
A voltmeter is always connected in parallel because if it is connected in series, it will change the value of potential difference to be measured by minimising the current in the circuit as it has very large resistance and hence will give faulty reading. Connecting it in parallel will not change the value of potential difference being measured as the voltmeter will draw negligible current and hence give correct reading of potential difference.
the voltmeter has high resistance , so if placed parallel in a circuit , very little current will go through it & most will go through the component to which it is parallel ....
a voltmeter has a high resistance ( in order to affect as little as possible the current that flows in the actual circuit when in parallel with it ).. if it was not connected in parallel then it could not measure potential across the particular circuit which is the purpose of the voltmeter ....
Voltmeters are put in parallel with the load in order to measure the potential differencebetween two *different* points.
If they are in parallel with the load, then at the first junction the current will split and flow into both paths (Kirchhoff's Laws). However, if current is flowing through the voltmeter, then it is not all flowing through the load, and the potential difference across the load would change when the voltmeter is added and removed. This is unfavourable. Therefore, the voltmeter must have a very high resistance so that current doesn't flow through it. (In reality, a little bit of current does still flow through, but it is insignificant in most cases.)
A _________ (V) _________ B
If a Voltmeter is connected in seris, (shown in the diagram) , the current that will be flowing through the conductor at A will be any hardly flowing at point B.A Voltmeter placed in seris will result in 0 potential because there will be minimal or no current flow after the Voltmeter (That would make conditions similar to an open circute) .This situation is just like you place a plastic instead of the voltmeter, will it conduct??NO because plastic has high restiance.
A ______ (V) ________ (BULB) ___ B
Suppose a Bulb(For Example) is connected after the voltmeter (which is arranged in seris) ,the bulb would not glow because the voltmeter has high resistance that would almost completly block the flow of current.This is not desiered to happen, actually makes no point by stoping the flow of current. The function of a voltmeter is to measure the potential difference accross two given points not stop or reduce the current.
RESISTANCE:The property of a substance to oppose current
When connected in parallel....
A ______ |__________| _____ (BULB) ___ B
(Take there is no gap between the wires here above ^^ )
The current flows to the Voltermeter and provides the reading and also same current would flow from A to B without disturbing the other electrical components.Also the BULB would glow.
Hence, voltmeters are connected in parallel.
The ammeter is connected in series so that the current flowing on the ammeter is same as in the resistance.
The voltmeter is connected in parallel so that the potential difference between resistance can be obtained.
The current flowing in series combination remains same whereas the potential difference gets divided according their resistances.
This above diagram shows that the ammeter is connected in series and voltmeter is connected in parallel. Note that the circuit is open and no current is flowing .But when it is switched on then the current starts flowing.