A wire is plastically deformed bent by supplying a force of 40 N over a distance of 0.8m. (The force moves in the direction in which the distance is measured). If the wire has a mass of 0.2 kg and a specific heat of 0.5 kJ/kg°C estimate the maximum increase in the average temperature of the wire
- A. 0.03°C
- B. 0.3°C
- C. 3°C
- D. 30°C
Answer: B. 0.3°C
Explanation: Work Done $W = 40 \times 0.8 = 32$ J. Heat $Q = mc\Delta T = 0.2 \times 500 \times \Delta T = 100 \Delta T$. $32 = 100 \Delta T \Rightarrow \Delta T = 0.32$.