Less than
Greater than
Equal to
None of these

Engineering Thermodynamics Which of the following is the correct statement of the second law of thermodynamics?

All of these
It is impossible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work
It is impossible to transfer heat from a body at a lower temperature to a higher temperature, without the aid of an external source
There is a definite amount of mechanical energy, which can be obtained from a given quantity of heat energy

Engineering Thermodynamics For the constant pressure and heat input, the air standard efficiency of gas power cycle is in the order

Dual cycle, Otto cycle, Diesel cycle
Diesel cycle, Otto cycle, Dual cycle
Dual cycle, Diesel cycle, Otto cycle
Otto cycle, Diesel cycle, Dual cycle

pv = m R T
pvn = C
pvγ = C
pv = C

Engineering Thermodynamics Work-done during adiabatic expansion is given by (where p1 v1, T1 = Pressure, volume and temperature for the initial condition of gas, p2, v2, T2 = Corresponding values for the final condition of gas, R = Gas constant, and γ = Ratio of specific heats)

[m R (T1 - T2)] /(γ - 1)
(p1 v1 - p2, v2)/(γ - 1)
[m R T1/(γ - 1)][1 - (p2, v2 /p1 v1)]
All of these