If the temperature of a wire is doubled then Young's modulus of elasti

1.	If the temperature of a wire is doubled then Young's modulus of elasticity ......
Answer» will also double. will become four times. reamin same. decreases. Solution :The CHANGE in length of wire occur due to change in temperature. `L _(t) = L _(0) (1 + alpha Delta T)` where `Delta T` is the change in temperature, `L _(0)=` original length, `L_(t)` is length at temperature `t, alpha=`COEFFICIENT of linear expansion. `therefore L _(T) - L _(0) = L _(0) prop Delta T` `therefore Delta L - L _(v) ~~ Delta T""...(1)` Now Young.s modulus `Y = ("Stress")/("Strain") = (F//A)/(Delta L //L _(0)) = (FL _(0))/( A Delta L )` `= (FL _(0))/( AL _(0) prop Delta T) ` [ From eq. (1)] `therefore Y prop (1)/(Delta T)` (ALl other terms are constant) Hence, Y decrease with increasing temperature.

Discussion