01.Which of the following is correct statement for 'Energy (E)'?
Ans. (d) : • Energy E is the property of system and it is the point function. • Change in energy between two states of a system is same for different path followed. • For point function dE = 0 ∫
02. Internal energy of system containing perfect gas depends on
Ans. (b) : Internal energy of a system containing perfect gas (ideal gas) depends on temperature only. U = f(T) [For ideal gas only
03Which of the following statements is correct for "Energy"
Ans. (a) : Note:-Option (a) is given by RPSC.
04. The heat capacity of the substance is given by expression:
Ans. (c) : Heat Capacity–Heat capacity or thermal capacity is a physical property of matter, defined as the amount of heat to be supplied to a given mass of a material to produce a unit change in its temperature. Heat capacity is an extensive property. It is denoted by C C = m × c (J/k) Where m → mass of the system c → Specific heat
05.Which of the following is NOT an intensive thermodynamic property?
Ans. (c) : Intensive Properties–An intensive property is a property of matter that depends only on the type of matter is a sample and not depends on the amount of mass. Example–Pressure, temperature, density, viscosity specific enthalpy, specific entropy, specific volume etc. Extensive Properties– An extensive property is a property that depends on the amount of matter in a sample. Example– Volume, enthalpy, entropy, mass energy etc.
06. A piston cylinder arrangement has air at 600 kPa, 290 K and volume of 0.01 m3 . During a constant pressure process, if it gives 54 kJ of work, the final volume must be
Ans. (a) : Given, P1 = 600 kPa T1 = 290 K W = 54 kJ V1 = 0.01 m3 V2 = ? W = PdV = P(V2 – V1) 54 × 103 = 600 × 103 (V2 – 0.01) V2 = 0.1 m3
07.Work done in a free expansion process is
Ans. (c) : From first law of thermodynamics δQ = dU + δW, since, for free expansion (T1 = T2) δQ = 0 and dU = 0 So, δW = 0
08. For an ideal gas, enthalpy is represented by
Ans. (b) : H = U + PV PV = mRT for unity mass, m = 1 H = U + mRT H = U + RT
09.Which one of the following represents the energy in storage?
Ans. (d) : Internal energy—Internal energy of a system is the sum of potential energy and kinetic energy of that system.
10. Heat transfer takes place as per
Ans. (c) : Heat transfer takes place as per second law of thermodynamics.