- Resistance in series (RS = R1+ R2 + R3)
Let R1, R2 and R3 are the three resistances that connect in series.
V = V1 + V2 + V3
As we know that V = IR So,
IR = IR1 + IR2 + IR3
IR = I (R1 + R2 + R3)
(RS = R1+ R2 + R3)
2. Resistance in parallel (1/RP = 1/R1 + 1/R2 + 1/R3)
Let three resistances R1, R2 and R3 are connect in parallel.
I = I1 + I2 + I3
As we know that V = IR or I = V/R
V/R = V/R1 + V/R2 + V/R3
V/R = V (1/R1 + 1/R2 + 1/R3)
1/RP = (1/R1 + 1/R2 + 1/R3)
DISADVANTAGE OF SERIES CIRCUIT
- If one electrical appliances stops working due to some defect, then all other appliances also stops working at that instant of time.
- All the electric appliances have only one switch due to which they cannot be turned on or off separately.
- The appliances do not get the same voltage as that of power supply line.
- In the series connection of the electrical appliances, overall resistances of circuit increases too much due to which current supply become low.