Question

Friends, I need some help.

Question) Two resistances are connected in series across a battery and consume a power P. If these are connected in parallel, then power consumed will be?


Please answer with full steps and explanation.
:)

Answer 1

The power delivered by the voltage source to either pair of resistors is inversely proportionto their combined resistance, i.e, if the combined resistance is greater, the power delivered is smaller.

pR=V2RpR=V2R

Now, recall that:

the series combination of two resistances is alwaysgreater than either individual resistance

the parallel combination of two resistances is alwaysless than than resistance of either individual resistance

For example, suppose that both resistors have the same value of resistance RR.

Now, if the two resistors are connected in series, the equivalent resistance is REQ=2RREQ=2R.

But, if the two resistors are connected in parallel, the equivalent resistance is REQ=R2REQ=R2.

Thus, the power for the series combination is:

pseries=12V2Rpseries=12V2R

Whilst the power for the parallel combination is:

pparallel=2V2Rpparallel=2V2R

In this case, the parallel combination dissipates 4 times the power of the series combination.