The diagram above shows three resistors connected across a cell of e.m.f. 1.8 V and internal resistance r. Calculate :
Current through `3Omega` resistor.

Explanation

Equivalent resistance of `3Omegaand1.5Omega` in parallel,
`R_(1)=(3xx1.5)/(3+1.5)Omega=1Omega`
Potential difference, across `R_(1)`
`rArrV_(1)=IR_(1)`
= `0.3xx1=0.3V`
`therefore` Current through `3Omega` resistor,
`I_(1)=V_(1)/3=0.3/3=0.1A`