A 2.00-kg copper rod is 49.00 cm long at 23°C.If 40,000 J are transferred to the rod by heat,what is its change in length? c_copper = 387 J/kg⋅°C and α_copper = 17 × 10−⁶/°C.

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Quizplus · Accepted Answer

The change in length is given by:$$\Delta L = \alpha L_i \Delta T$$where:* $\alpha$ is the coefficient of linear expansion* $L_i$ is the initial length* $\Delta T$ is the change in temperatureWe are given:* $\alpha = 17 	imes 10^{-6}/°C$* $L_i = 49.00 cm$* $\Delta T = \frac{40,000 J}{2.00 kg 	imes 387 J/kg⋅°C} = 51.68°C$Substituting these values into the equation, we get:$$\Delta L = (17 	imes 10^{-6}/°C)(49.00 cm)(51.68°C) = 0.043 cm$$Therefore, the change in length is 0.043 cm.

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