Which statement is not true for a steam turbine when compared to steam...
Explanation:
Comparison between steam turbines and steam engines:
1. Thermodynamic efficiency: Both steam turbines and steam engines can achieve high thermodynamic efficiency. This means that they can convert a large percentage of the thermal energy in steam into useful work. Therefore, option 'a' is true for both steam turbines and steam engines.
2. Power output per unit weight: Steam turbines generally have a higher power output per unit weight compared to steam engines. This is because steam turbines operate at higher speeds and have a more compact design. The high-speed rotation of the turbine blades allows for efficient energy conversion. On the other hand, steam engines are bulkier and operate at lower speeds, resulting in lower power output per unit weight. Therefore, option 'b' is true for steam turbines and not true for steam engines.
3. Flywheel weight: In steam turbines, the flywheel is not as critical as in steam engines. The flywheel in a steam engine helps to maintain a steady rotational speed and smooth out any variations in power output. However, in steam turbines, the high-speed rotation of the turbine rotor itself provides the necessary inertia and stability. Therefore, steam turbines do not require a heavy flywheel like steam engines. Hence, option 'c' is not true for steam turbines.
4. Overload capacity: Steam turbines have the capacity to carry considerable overloads with only a slight reduction in efficiency. This means that they can handle sudden increases in power demand without significant performance degradation. Steam engines, on the other hand, may experience a more noticeable reduction in efficiency when overloaded. Therefore, option 'd' is true for steam turbines and not true for steam engines.
Conclusion:
Among the given statements, option 'c' is not true for steam turbines. Steam turbines do not require a heavier flywheel compared to steam engines.
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