The total resistance of the original light bulbs are: 1/(1/R1 + 1/R2) The total resistance after the addition of the third light bulb is: 1/(1/R1 + 1/R2 + 1/R3) Therefore, if the resistance of the third light bulb is not infinity, 1/R3 will be greater than 0 and and adding a greater-than-0 number to the denominator of a fraction will lower the value of the fraction. Therefore, the total resistance will lower. Intuitively, you can think that adding a third bulb is opening up another possible path for electrons to flow through, therefore decreasing total impediment to electron flow.
"http://www.tpub.com/neets/book1/chapter3/1-26.htm" This site explains how to calculate the resistance, but it decreases the resistance when you add more.
Adding anything(yes,even a superconductor) to a any circuit adds resistance, especially devices that are by there very nature high resistors
Ohm's Law says Voltage = Current x Resistance With constant voltage, an increase in resistance decreases the current. Now the load can be added in two basic ways. If the load is added in series the resistance will increase. If you add load in parallel the resistance will decrease and the current will increase from the source.
in a parallel circuit, the relationship of resistance is thus: 1/R1 + 1/R2 = 1/RT where R1 and R2 are two resistors in parallel and RT is the total resistance in the circuit: Using this, as more branches are added, the resistance decreases This is because there is more ways for the current to flow and thus using the analogy of a water flow with a constraint on it (resistor in electrical circuits), a whole load of streams with the same constraint on each will allow more water through than one large stream with the same small constraint on it.
Adding any additional element in parallel will reduce the combined resistance. Do some sample calculations to get a "feel" for this: Total resistance (R) is calculated as 1/R = 1/R1 + 1/R2 + 1/R3... In other words, take the reciprocal of the individual resistances, add them, and then take the reciprocal of the result.
You raise the total resistance by that amount if added in series to a circuit. If you add them in parallel to a circuit then that total resistance will be less than the total of the added circuit.
Does it? See Related Links
Total resistance decreases.
In the circuit where the DC motor is added, it was not specified whether the motor was added in series or in parallel to circuit elements. If it was added in series, it will increase circuit resistance and it will cause circuit current to go down. In parallel, the motor will reduce total circuit resistance, and circuit current will increase.
reduces it from 1/2 to 1/3rd
Current decreasesWhen voltage remains constant and resistance increases the current in the circuit will reduce.More informationV=IRwhere V is voltage,I is current andR is resistance.From the above equation,R=V/I, and hence resistance is indirectly proportional to current.Therefore, an increase in resistance would have the effect of decreased current.NB: this holds true only as long as the voltage remains constant.Another opinionHowever, this is only true in the case of a circuit connected in series.When circuits are connected in parallel, the opposite happens. If there is an increase in the amount of resistors in parallel, the total resistance of the circuit then decreases and the current increases subsequently.Yet another viewNo, that's not stated right.If more resistors are added in parallel - so that the circuit's overall total resistance decreases and its total current increases - that is NOT in any way the opposite of what this question is asking about...Let's make this crystal clear, so that there is no confusion: "an increase in the amount of resistors" is NOT the same as "an increase in resistance".So a parallel circuit behaves EXACTLY the same as a series circuit: if its overall resistance increases, the overall current going through the parallel circuit decreases AND if its overall resistance decreases, the overall current going through the parallel circuit increases.Actually, the second opinion is correctIn a parallel circuit, there are more branches to allow electrons back to the power supply, so current increases. With more resistors in a circuit, the overall resistance in a parallel circuit DECREASES.In a series circuit, current is the same throughout. So if more resistors are added, resistance INCREASES and so current DECREASES.
The total resistance of the circuit increases. hence the new resistance after adding the resistance will be new resistance = old resistance + added Resistance There is a small mistake in the question. The second word is 'changes' not 'charges'
"http://www.tpub.com/neets/book1/chapter3/1-26.htm" This site explains how to calculate the resistance, but it decreases the resistance when you add more.
Adding anything(yes,even a superconductor) to a any circuit adds resistance, especially devices that are by there very nature high resistors
Ohm's Law says Voltage = Current x Resistance With constant voltage, an increase in resistance decreases the current. Now the load can be added in two basic ways. If the load is added in series the resistance will increase. If you add load in parallel the resistance will decrease and the current will increase from the source.
If a fourth bulb were added in a similar way to the three existing bulbs, the resistance in the circuit would go up if the bulbs were series connected, and it would go down if the bulbs were parallel connected.
• In a parallel circuit, there are junctions in the circuit so the current can flow around the circuit in more than one way. • In a series circuit the current decreases as more bulbs are added. •In a parallel circuit, as more bulbs are added, the current increases. • This is because bulbs added in parallel offer less resistance