The variation of length of two metal rods A and B with change in temperature is shown in Fig. the coefficient of linear expansion `alpha_A` for the metal A and the temperature T will be? ( alpha_(A)=3x10^(-6)/ C )

Options

A. `alpha_(A) = 3 xx 10^(-6 )//^(@)C, 500^(@)C`
B. `alpha_(A) = 3 xx 10^(-6 )//^(@)C, 222.22^(@)C`
C. `alpha_(A) = 27 xx 10^(-6) //^(@)C, 500^(@)C`
D. `alpha_(A) = 27 xx 10^(-6) //^(@)C, 222.22^(@)C`

Answer

D

Explanation

Slope of the line `A = (1006 - 1000)/(T) = (DeltaL)/(DeltaT)`
`(6)/(T) = 1000mm alpha_(A)` ……..(1)
similarly for `B` line
`(2)/(T) = 1002mm alpha_(B)` …….(2)
From `(1)` and `(2) alpha_(A) = 3alpha_(B)`