For the part of the circuit gives in figure, find the current following through `2Omega` resistor:

Options

A. `1 A`
B. `3A`
C. `4A`
D. information insufficient

Answer

A

Explanation

Let potential of point O be V, then write the potential of various points in terms of V as shown in the figure

Apply junction rule at O.
`(V-6-10)/(2)+(V-8-2)/(1)=3`
`or V-16+2(V-10)=3xx2`
or 3V=42 or V=14 vot
Current through `2Omega` resistor,
`I=(V-6-10)/(2)=(14-6-10)/(2)=-1A`
-ve sign shows that current is coming towards O. i.e., opposite to our assumed direction.