Compare the power used in the `2Omega` resistor in each of the following circuits:
i] a 6 V battery in series with `1Omegaand2Omega` resistors, and
ii] a 4 V battery in parallel with `12Omegaand2Omega` resistors.

Explanation

i] Potential difference M = 6 V
Here `1Omegaand2Omega` resistors are connected in series,
`therefore` equivalent resistance of the circuit [R] = 1 + 2 = `3Omega`,
According to Ohm.s law
`V=IRorI=V/R=6/3=2A`
the current through the circuit [I] = 2A
Now the power used in the `2Omega` resistor
Power = `I^(2)R=2xx2xx2=8W`
ii] Potential difference, V = 4V
`12Omegaand2Omega` resistors are connected in parallel. The voltage across each component of a parallel circuit remains the same. Hence, the voltage across `2Omega` resistor will be 4 V. Power consumed by `2Omega` resistor is given by
`P=V^(2)/R=4^(2)/2=8W`
`therefore` the power used by `2Omega` resistor is 8W.