Two metallic wires made from copper have same length but the radius of wire 1 is half of that of wire 2. The resistance of wire 1 is R. If both the wires are joined together in series, the total resistance becomes

Two metallic wires made from copper have same length but the radius of

1.	Two metallic wires made from copper have same length but the radius of wire 1 is half of that of wire 2. The resistance of wire 1 is R. If both the wires are joined together in series, the total resistance becomes
A.	2R
B.	\(\frac{{\rm{R}}}{2}\)
C.	\(\frac{5}{4}{\rm{R}}\)
D.	\(\frac{3}{4}{\rm{R}}\)
Answer» D. \(\frac{3}{4}{\rm{R}}\)