Two resistors of and are connected in series with an unknown resistor

PHYSICS · Single correct · A Level · Physics · Electricity · Electricity

Problem

Two resistors of

5\,\Omega

and

8\,\Omega

are connected in series with an unknown resistor

R_x

. The series combination is connected to a

24\,\text{V}

ideal source and the current in the circuit is

1.0\,\text{A}

. Determine the value of

R_x

. (a)

19\,\Omega

(b)

11\,\Omega

(c)

13\,\Omega

(d)

21\,\Omega