Q1: Rankine cycle comprises of two isothermal and two __________ processes.

ANS:D - none of these

The Rankine cycle comprises of two isothermal and two isentropic processes. In the Rankine cycle, a thermodynamic cycle commonly used in steam power plants, the working fluid undergoes four main processes:

1. Isentropic Compression: The working fluid is compressed isentropically (i.e., with no change in entropy) from a low-pressure state to a high-pressure state. This is typically achieved in the compressor of the power plant.
2. Isobaric Heat Addition: The compressed working fluid is then heated at constant pressure in the boiler, where it undergoes an isobaric (constant pressure) process. During this process, heat is added to the working fluid, increasing its temperature and energy.
3. Isentropic Expansion: The high-pressure, high-temperature fluid leaving the boiler enters the turbine, where it expands isentropically, converting part of its internal energy into mechanical work. This process drives the turbine, which, in turn, drives the generator to produce electricity.
4. Isobaric Heat Rejection: After expansion in the turbine, the low-pressure, low-temperature working fluid is condensed back into liquid form in the condenser, where it undergoes an isobaric process at constant pressure. Heat is rejected from the working fluid to a cooling medium, usually water from a cooling tower or a river, and the fluid is returned to the boiler to restart the cycle.