Parallel circuits

Putting electrical components in parallel is a common practice.

House circuits are also parallel. This is an example of bulbs in a parallel circuit:

 

This way you can turn one light bulb on at a time if the main switch is on. If one of the bulbs blows the other will still be working because the circuit will still be complete. That is why we don’t place house circuits in series because if one bulb blows, everything will turn off.

Kirchhoff’s second law:

Kirchhoff’s second law is an electrical application of the law of conservation of energy. It states that:

“In any closed loop in a circuit the sum of the e.m.f.s is equal to the sum of p.d.s”

Remember: e.m.f. is the energy per unit charge transferred into electrical energy.

p.d. is energy transferred per unit charge from electrical energy.

 

Resistors in parallel:

 

Circuit resistance when all items are switched on: =supply p.d / total current.

=230/1.15A=200Ω

Total resistance in parallel circuits:

1/RT= 1/R1 + 1/R2 + 1/R3.....

 

 Sajeel