Q47 (2026)
A thermodynamic system is taken through the cyclic process ABC as shown in the figure. The total work done by the system during the cycle ABC is ____ J.
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### Related Formula
$$W_{\text{cycle}} = \text{Area enclosed by the P-V cycle}$$
### Core Logic
In a P-V diagram, the work done in a cyclic process is equal to the area of the enclosed loop. Since the cycle ABC is clockwise (A $\rightarrow$ B $\rightarrow$ C $\rightarrow$ A), the net work done by the system is positive.
### Step 1: Calculate the Area
The shape ABC is a right-angled triangle.
Base of the triangle $= \Delta V = V_C - V_A = 5 - 2 = 3 \text{ m}^3$
Height of the triangle $= \Delta P = P_B - P_C = 300 - 100 = 200 \text{ Pa}$
### Step 2: Compute Work Done
$$W = \frac{1}{2} \times \text{Base} \times \text{Height}$$
$$W = \frac{1}{2} \times 3 \text{ m}^3 \times 200 \text{ Pa}$$
$$W = 3 \times 100 = 300 \text{ J}$$
### Pattern Recognition
Always verify axis units (kPa, atm, Liters, cc) before blindly multiplying area. Here units are cleanly in standard SI (Pa and $m^3$), so $1 \text{ Pa} \cdot 1 \text{ m}^3 = 1 \text{ Joule}$.
### Evaluation Rubric / Model Answer
null
### Chapter Mix
Class 11 Physics: Thermodynamics
