Thermodynamics Set 4

Mechanical Engineering

Practice Mode Previous Next
On This Page

This set of Thermodynamics Multiple Choice Questions & Answers (MCQs) focuses on Thermodynamics Set 4

Q1 | The internal energy of a gas is a function of temperature". Which of the following name is associated with the above law?
  • Regnault
  • Dalton
  • Boyle
  • Charle
  • Joule
Answer: Joule
Q2 | The solubility of a gas in a liquid at small concentration is represented by
  • Joules equation
  • Van der Waal's equation
  • Henry's law
  • Claperyon equation
  • Roults law
Answer: Henry's law
Q3 | A scavenging pump is used in
  • Pulsejet
  • vapour compression cycles
  • two stroke spark ignition engines
  • steam engines
  • four stroke compression ignition engines
Answer: two stroke spark ignition engines
Q4 | The difference between two specific heats of a gas is equal to universal constant when
  • 1 mole of gas is heated
  • 1 gm molecule of gas is heated
  • 1 gm of gas is heated
  • Pulsejet
  • any amount of gas is heated
Answer: 1 gm molecule of gas is heated
Q5 | Which of the following is a non-petroleum fuel?
  • Diesel oil
  • Petrol
  • Naphtha
  • Alcohol
  • All of the above
Answer: Alcohol
Q6 | The average pressure on the walls of a vessel will be doubled if the
  • average velocity of the molecules in it is doubled
  • the number of molecules in the vessel is doubled
  • Pulsejet
  • the mass of each molecule is halved
  • the mass of each molecule is doubled
Answer: the number of molecules in the vessel is doubled
Q7 | The fastest moving gas molecules are those of
  • Pulsejet
  • Oxygen
  • Hydrogen
  • Nitrogen
  • Chlorine
Answer: Hydrogen
Q8 | which of the following set of quantities contains intensive variables?
  • Kinetic energy, potential energy and internal energy
  • Pulsejet
  • Work, energy and weight
  • Mass, volume and area
  • Pressure, temperature and density
Answer: Pressure, temperature and density
Q9 | A system
  • Is a specified region, not necessarily of constant volume, where transfer of energy and/or mass are to be studied
  • Is a region of constant mass and only energy is allowed to cross the boundaries
  • Cannot transfer either energy or mass to or from the surroundings
  • Has a mass transfer across its boundaries and the mass within the system is not constant
  • None of the above
Answer: Is a specified region, not necessarily of constant volume, where transfer of energy and/or mass are to be studied
Q10 | Transformer oil having kinematic viscosity of 3.66 x 10-6 m2/s flows through a tube 8 mm diameter at velocity of 0.6 m/s. The value of Reynolds number of flow would be
  • 1510
  • 1000
  • 1600
  • 1415
  • 1310
Answer: 1310
Q11 | An isentropic process is always
  • Irreversible and adiabatic
  • Reversible and isothermal
  • Frictionless and irreversible
  • Reversible and adiabatic
  • None of the above
Answer: Reversible and adiabatic
Q12 | In a reversible polytropic process
  • The entropy remains constant
  • Some heat transfer occurs
  • The internal energy remains constant
  • The temperature remains constant
  • The ethalpy remains constant
Answer: The entropy remains constant
Q13 | A gas which obeys kinetic theory perfectly is known as
  • Monoatomic gas
  • Perfect gas
  • Diatomic gas
  • Real gas
  • Pure gas
Answer: Perfect gas
Q14 | An automobile heats up while lying in a parking 10 ton a sunny day. The process can be assumed to be
  • isothermal
  • isometric
  • isobaric
  • Pulsejet
  • isentropic
Answer: isobaric
Q15 | The efficiency of a Carnot engine is given as 0.75. If the cycle direction is reversed, what will be the value of COP of reversed Carnot cycle
  • 0.33
  • 0.25
  • 1.33
  • 0.75
  • 4
Answer: 0.33
Q16 | Which rays have the least wavelength?
  • Infra-red
  • Ultraviolet
  • Radio
  • Cosmic rays
  • X-rays
Answer: Cosmic rays
Q17 | The difference between two specific heats of a gas is equal to universal gas constant
  • When 1 gm molecule heated
  • When 1 molecule of gas is heated
  • When 1 gm of gas is heated
  • When any amount of gas is heated
Answer: When 1 gm molecule heated
Q18 | 1 cu-m of steam having dryness franction 0.85 at 12 ata mixes with 1.5 kg of water at 12?C at constant pressure. The dryness fraction of resulting steam would be
  • 0.6
  • 0.5
  • 0.85
  • 0.637
  • 0.75
Answer: 0.637
Q19 | In centrifugal compressors, the ratio of outlet whirl velocity to blade velocity at outlet is known as
  • Feedback factor
  • Slip factor
  • Reheat factor
  • Gauge factor
  • Velocity factor
Answer: Slip factor
Q20 | In case of centrifugal compressors the phenomenon of unsteady, periodic and reversed flow is known as
  • Surging
  • Stalling
  • Choking
  • Either of above
  • None of the above
Answer: Surging
Q21 | A Rankine cycle working with saturated steam differs thermodynamically from a Carnot cycle only in the fact that
  • The Carnot cycle cannot be used for vapour
  • Steam is not the working substance for Carnot cycle
  • There are more than two sources of heat in Rankine cycle
  • Heat is supplied to the water at temperatures below the maximum temperature of the cycle
  • None of the above
Answer: Heat is supplied to the water at temperatures below the maximum temperature of the cycle
Q22 | In case of ideal triatomic gas, the ratio of specific heats Cp/Cv would be
  • 1
  • 1.33
  • 1.4
  • 1.41
  • 1.67
Answer: 1.33
Q23 | During adiabatic expansion which of the following remains constant
  • Internal energy
  • Temperature
  • Entropy
  • None of the above
  • Pulsejet
Answer: Entropy
Q24 | Which of the following is a boiler accessory?
  • Water level indicator
  • Economiser
  • Pulsejet
  • Stop valve
  • Fusible plug
Answer: Economiser
Q25 | Draught ensures supply of
  • Air for combustion
  • Feed water
  • Coad to the boiler
  • Superheated steam
  • Isothermal
Answer: Air for combustion
Previous Next