Question
Two long straight parallel wires, carrying (adjustable) current $${I_1}$$ and $${I_2},$$ are kept at a distance $$d$$ apart, If the force $$'F'$$ between the two wires is taken as ‘positive’ when the wires repel each other and ‘negative’ when the wires attract each other, the graph showing the dependence of $$'F',$$ on the product $${I_1}\,{I_2},$$ would be :
A.
B.
C.
D.
Answer :
Solution :
$$\eqalign{ & {I_1}\,{I_2} = {\text{Positive}} \cr & \left( {{\text{attract}}} \right)F = {\text{Negative}} \cr & {I_1}\,{I_2} = {\text{Negative}} \cr & \left( {{\text{repell}}} \right)F = {\text{Positive}} \cr} $$
Hence, option (A) is the correct answer.
$$\eqalign{ & {I_1}\,{I_2} = {\text{Positive}} \cr & \left( {{\text{attract}}} \right)F = {\text{Negative}} \cr & {I_1}\,{I_2} = {\text{Negative}} \cr & \left( {{\text{repell}}} \right)F = {\text{Positive}} \cr} $$
Hence, option (A) is the correct answer.