Two wires of same length and radius are joined end to end and loaded. The Young.s modulii of the materials of the two wires are Y_(1) and Y_(2). If the combination behaves as a single wire them its Young.s modulus is

Two wires of same length and radius are joined end to end and loaded.

1.	Two wires of same length and radius are joined end to end and loaded. The Young.s modulii of the materials of the two wires are Y_(1) and Y_(2). If the combination behaves as a single wire them its Young.s modulus is
Answer» Solution :`e=e_(1) +e_(2)" but " e=(F(2L))/(AY_(EQ)), e_(1)=(FL)/(AY_(1)), e_(2)=(Fl)/(AY_(2))` `(F(2l))/(AY_(eq))=(Fl)/(AY_(1))+(Fl)/(AY_(2))` `(2)/(Y_(eq))=(1)/(Y_(1))+(1)/(Y_(2)) RARR Y_(eq)=(2Y_(1)Y_(2))/(Y_(1)+Y_(2))`