In the following figures $(a)$ to $(d)$,the variation of volume with change of pressure is shown. The gas is taken along the path $A B C D A$. The change in internal energy of the gas will be .......

Calculate the heat absorbed by the system in going through the process shown in the figure.

The figure shows the $P-V$ plot of an ideal gas taken through a cycle $ABCDA.$ The part $ABC$ is a semicircle and $CDA$ is half of an ellipse. Then,

In a thermodynamic process,the pressures and volumes corresponding to some points in the figure are $P_A = 3 \times 10^4 \, Pa$,$V_A = 2 \times 10^{-3} \, m^3$,$P_B = 8 \times 10^4 \, Pa$,and $V_D = 5 \times 10^{-3} \, m^3$. In process $AB$,$600 \, J$ of heat is added,and in process $BC$,$200 \, J$ of heat is added to the system. The change in the internal energy in process $AC$ would be .... $J$.

$A$ monoatomic ideal gas goes through a cyclic process as shown in the figure. The efficiency of this process is (in $\%$)

During the thermodynamic process shown in the figure for an ideal gas: