Can someone explain me how to do this question? Thanks.

1 Answer
Feb 25, 2018

A.

Explanation:

When,two resistors are connected in series,current flowing through them is the same.

Now,when X and Y are connected in series,if 2A current is flowing through them,so from the graph, when I = 2A, for X ,Voltage = 4V,so its resistance = 4/2=2 Omega,

And,for Y at I=2 V=10

So,total voltage of the circuit is 4+10=14V

if the resistance of Y is r, then we can say, 14/(2+r) = 2

so, r=5 Omega

So,total resistance of combination is 2+5=7 Omega