Physics

Problem

A slightly conical wire of length

l

and radii

r_1

and

r_2

is stretched by two forces

F

applied parallel to length in opposite directions and normal to end faces. If

Y

denotes the young modulus then the elongation in the wire is: (a)

\frac{Fl}{2\pi r_1 r_2 Y}

(b)

\frac{Fl}{\pi r_1 r_2 Y}

(c)

\frac{2Fl}{\pi r_1 r_2 Y}

(d) None