Two conductors are made of the same material

cbse
current-electricity

#1

Two conductors are made of the same material and have the same length. Conductor A is a solid wire of diameter 1 mm. Conductor Sis a hollow tube of outer diameter 2 mm and inner diameter 1 mm. Find the ratio of resistance $R_{ A }$ to $R_{ B }$.


#2

The resistance of first conductor

The resistance of second conductor,

Now, the ratio of two resistors is given by