A copper wire of negligible mass, length (l), corss-sectionalarea (A) is kept on a smooth horizontal table with one end fixed, a ball of mass .m. is attached at other end. The wire and the ball are rotated with angular velocity .omega.. If wire elongates by Deltal then find Young.s modulus of wire. If on increasing the angular velocity from omega to omega^(1) the wire breakdown, obtain breaking stress (Deltal lt lt l)

A copper wire of negligible mass, length (l), corss-sectionalarea (A)

1.	A copper wire of negligible mass, length (l), corss-sectionalarea (A) is kept on a smooth horizontal table with one end fixed, a ball of mass .m. is attached at other end. The wire and the ball are rotated with angular velocity .omega.. If wire elongates by Deltal then find Young.s modulus of wire. If on increasing the angular velocity from omega to omega^(1) the wire breakdown, obtain breaking stress (Deltal lt lt l)
Answer» Solution :(a) `r=l+Deltal` `F=T=mrw^(2)=m(l+Deltal)omega^(2)` as `Deltal` in SMALL, `F=mlomega^(2)""y=(Fl)/(AE)""y=((mlomega^(2))l)/(A Deltal)` (b) We know Breakingstress `=("Breaking FORCE")/("Area of cross section")=(ml omega^(1^(2)))/(A)`