Current Electricity
4.0 Combination of Resistors
4.0 Combination of Resistors
In series
- Current through each resistance is same.
- Sum of potential differences across individual resistors is equal to total potential difference. $$V = {V_1} + {V_2} + {V_3}$$
- Equivalent resistance is equal to sum of individual resistance. $${R_s} = {R_1} + {R_2} + {R_3}$$
For $n$ resistors arrangement, equivalent resistance is,$$ \Rightarrow {R_s} = {R_1} + {R_2} + {R_3} + ....... + {R_n}$$
In parallel
- Potential drop across each resistance is same.
- Total current is equal to sum of individual resistances.$$I = {I_1} + {I_2} + {I_3}$$
- Reciprocal of equivalent resistance is equal to sum of reciprocalsof the individual resistance.$$\frac{1}{{{R_s}}} = \frac{1}{{{R_1}}} + \frac{1}{{{R_2}}} + \frac{1}{{{R_3}}}$$
For $n$ resistors arrangement, equivalent resistance is, $$ \Rightarrow \frac{1}{{{R_s}}} = \frac{1}{{{R_1}}} + \frac{1}{{{R_2}}} + \frac{1}{{{R_3}}} + ....... + \frac{1}{{{R_n}}}$$
