Question

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

Answer 1

`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`