(a) Three resistors `3Omega, 4Omega, and 12Omega` are connected in parallel. What is the effective resistance of the combination?
(b) If the combination is connected to a battery of emf 6V and internal resistance `0.5Omega`, find the current drawn from the battery and terminal potential difference across the battery.

Explanation

Let `R_(1)= 3Omega, R_(2)= 4Omega " &" R_(3)=12Omega` are three resistances of the resistors. Effective resistance in parallel `(1)/(R_(P))= (1)/(R_(1)) + (1)/(R_(2)) + (1)/(R_(3))`
`(1)/(R_(P))= (1)/(3) + (1)/(4) + (1)/(12)= (96)/(144)`
`R_(P)= 1.5Omega`
Current drawn `I= (E )/(R + r) = (6)/(1.5 + 0.5)= 3A`
`V= IR_(P) = 3 Omega xx 1.5A= 4.5V`