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Question
Differentiate between resistances in series and parallel.
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Solution
| Resistances in Series | Resistances in Parallel | ||
| 1 | In this type of connection, the resistances are connected one after the other such that the same amount of current flows through each resistance. | 1 | In this type of connection, the resistances are connected between two common points such that the potential difference across each resistor is the same. |
| 2 | For n number of resistors connected in series, the effective resistance RS is equal to the sum of the individual resistors. RS = R1 + R2 + R3 + R4+ …… Rn |
2 |
For n number of resistors connected in pparallel, the reciprocal of the effective resistance (Rp) is equal to the sum of the reciprocals of the individual resistances. `1/R_p=1/R_1+1/R_2+..............+1/R_p`
|
| 3 | The effective resistance in series combination is greater than the individual resistances. | 3 | The effective resistance in parallel combination is less than the individual resistances in the combination. |
| 4 | It is used to decrease the current in the circuit. | 4 | It is used to increase the current in the circuit. |
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