Question

suppose you want to use a microwave, a toaser, a coffee maker and a clock radio in your kitchen. You get one of those little multiple plug devices and plug them all in the same outlet. Why does your circuit breaker blow when you turn them all on at once? Explain, in terms of series/parallel circuits, what is happening when all te appliances are on at the same time.

Answer 1

The circuit breaker blows due to overloading means a large amount of current flows through a circuit when we switch ON.

The reason of this large current can be understand as follows -

suppose the mocrowave has a resistance = R1

a toaster has a resistance = R2

resistance of coeffee maker = R3

clock radio has a resistance = R4

when they are connected to the same multiplug, we are connecting all the equipment in parallel because the potential difference across the each equipment is the same.

so the equivalent resistance of the circuit is -

1 / R = 1 / R1 + 1/ R2 + 1/ R3 + 1/R4

so, value of R is very low in comparision with the normal resistance of the equipements.

current I = V / R

when R is low, I will be large.

so, the circuit breaker blows when we switch ON the switch.