Two rods of the same length, have radii in the ratio `3:4` Their densities are respectively `8000` and `9000 kg//m^(3)`. Their specific heats are in the ratio of `2:3`. When the same amount of heat is supplied to both, the changes in their lengths are in the ratio. (If their linear coefficients are in the ratio `5:6`)A. `1:1`B. `5:2`C. `5:12`D. `12:5`

Two rods of the same length, have radii in the ratio `3:4` Their densi

1.	Two rods of the same length, have radii in the ratio `3:4` Their densities are respectively `8000` and `9000 kg//m^(3)`. Their specific heats are in the ratio of `2:3`. When the same amount of heat is supplied to both, the changes in their lengths are in the ratio. (If their linear coefficients are in the ratio `5:6`)A. `1:1`B. `5:2`C. `5:12`D. `12:5`
Answer» Correct Answer - B `Q = msDeltatheta, m = rhopir^(2)l` `Delta theta = (Deltal)/(lalpha) rArr (Deltal_(1))/(Deltal_(2)) = (rho_(2))/(rho_(1)) xx (r_(2)^(2))/(r_(1)^(2)) xx (s_(2))/(s_(1)) xx (alpha_(1))/(alpha_(2))`

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