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A cylindrical copper rod of length 0.60m...

A cylindrical copper rod of length 0.60m and cross-sectional area 6.0 `cm^(2)` is insulated along its side. The ends are held at a temperature difference of `100^(@)C` by having one end in a water -ice mixture and the other in a mixture of boiling water and steam. At what reate (a) is energy conducted by the rod and (b) does the ice melt ?

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To solve the problem step by step, we will first calculate the rate of energy conducted by the copper rod and then determine the rate at which the ice melts. ### Given Data: - Length of the copper rod, \( L = 0.60 \, \text{m} \) - Cross-sectional area, \( A = 6.0 \, \text{cm}^2 = 6.0 \times 10^{-4} \, \text{m}^2 \) - Temperature difference, \( \Delta T = 100 \, ^\circ C \) - Thermal conductivity of copper, \( k = 401 \, \text{W/m} \cdot \text{K} \) ### Part (a): Rate of Energy Conducted by the Rod 1. **Use Fourier's Law of Heat Conduction**: \[ P = \frac{k \cdot A \cdot (T_H - T_C)}{L} \] Where: - \( P \) is the rate of heat transfer (W) - \( k \) is the thermal conductivity (W/m·K) - \( A \) is the cross-sectional area (m²) - \( T_H - T_C \) is the temperature difference (K) - \( L \) is the length of the rod (m) 2. **Substitute the values into the formula**: \[ P = \frac{401 \, \text{W/m·K} \cdot 6.0 \times 10^{-4} \, \text{m}^2 \cdot 100 \, \text{K}}{0.60 \, \text{m}} \] 3. **Calculate the numerator**: \[ 401 \cdot 6.0 \times 10^{-4} \cdot 100 = 24060 \, \text{W·m}^2 \] 4. **Calculate the rate of heat transfer**: \[ P = \frac{24060}{0.60} = 40100 \, \text{W} \] 5. **Convert to Joules per second**: \[ P = 40 \, \text{J/s} \] ### Part (b): Rate at which the Ice Melts 1. **Use the formula for the rate of melting ice**: \[ \frac{dm}{dt} = \frac{P}{L_f} \] Where: - \( \frac{dm}{dt} \) is the mass of ice melted per second (g/s) - \( L_f \) is the latent heat of fusion of ice (approximately \( 333 \, \text{J/g} \)) 2. **Substitute the values**: \[ \frac{dm}{dt} = \frac{40 \, \text{J/s}}{333 \, \text{J/g}} \] 3. **Calculate the rate of melting**: \[ \frac{dm}{dt} \approx 0.12012 \, \text{g/s} \approx 0.12 \, \text{g/s} \] ### Final Answers: - (a) The rate of energy conducted by the rod is **40 J/s**. - (b) The rate at which the ice melts is **0.12 g/s**.
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