Question 1

Which of the following statement is true?&#10;A)to the left of saturated solid line is the solid region&#10;B)between saturated solid line and saturated liquid line with respect to solidification there exists the solid-liquid mixture region&#10;C)between two saturated liquid lines is the compressed liquid region&#10;D)all of the mentioned

Accepted Answer

All the statements provided are true with respect to a phase diagram, which visually represents the states of matter (solid, liquid, gas) of a substance under different conditions of temperature and pressure. A) describes the phase to the left of the solidus line, which is the solid phase. B) describes the region between the solidus and liquidus lines, where both solid and liquid phases coexist during the melting or solidification process. C) is slightly misstated but generally refers to the region in a phase diagram where liquid is under higher pressure than its vapor pressure at a given temperature, typically not delineated by "saturated liquid lines" but understood as the region below the liquid-vapor equilibrium line (or to the left of the vapor pressure curve in a T-v diagram) at temperatures below the critical point. However, the essence of the statements aligns with the understanding of phase diagrams and the behavior of substances under various conditions.

Question 2

The greater the temperature, the is the vapour pressure.&#10;A)lower&#10;B)higher&#10;C)depends on the substance&#10;D)none of the mentioned

Accepted Answer

The vapor pressure of a substance increases with temperature because as temperature increases, more molecules have enough energy to escape from the liquid phase into the vapor phase, thus increasing the vapor pressure.

Question 3

Phase change occurs at&#10;A)constant pressure&#10;B)constant temperature&#10;C)constant pressure and temperature&#10;D)none of the mentioned

Accepted Answer

constant pressure and temperature&#10;

Question 4

Which of the following statement is true?&#10;A)saturation temperature is a function of pressure&#10;B)saturation pressure is a function of temperature&#10;C)both of the mentioned&#10;D)none of the mentioned

Accepted Answer

Both statements A and B are true because in thermodynamics, the saturation temperature of a substance changes with pressure, and similarly, the saturation pressure changes with temperature. This relationship is fundamental in understanding phase change processes of substances.

Question 5

At absolute zero, an isotherm and an adiabatic are identical.

Accepted Answer

At absolute zero, there is no thermal energy, so no heat exchange occurs, making the isotherm (constant temperature) and adiabatic (no heat exchange) processes identical.

Question 6

When the heat transferred isothermally&#10;A)doesnot, can, without&#10;B)exists, cannot, without&#10;C)exists, can, with&#10;D)none of the mentioned

Accepted Answer

The answer of When the heat transferred isothermally&#10;A)doesnot, can, without&#10;B)exists,...

Question 7

During a fluid flow, the temperature is developed due to&#160;&#10;A)increase in density&#10;B)change in pressure&#10;C)translational kinetic energy&#10;D)fluid level

Accepted Answer

The temperature in a fluid flow is primarily developed due to the translational kinetic energy of the fluid molecules, which is related to their velocity and movement.

Question 8

The equation for the average kinetic energy is&#160;&#10;A)0.5 kt&#10;B)1.5 kt&#10;C)2.5 kt&#10;D)3.5 kt

Accepted Answer

The average kinetic energy of a molecule in an ideal gas is given by the equation (3/2)kT, where k is the Boltzmann constant and T is the temperature in Kelvin. This simplifies to 1.5 kT, making option B correct.

Question 9

Entropy occurs due to &#160;&#10;A)change in macroscopic variables&#10;B)volumetric changes only&#10;C)mass changes only&#10;D)temperature only

Accepted Answer

Entropy changes can occur due to a variety of reasons, not limited to volumetric, mass, or temperature changes alone. It is a measure of disorder or randomness, which can be affected by changes in any macroscopic variables, including pressure, volume, temperature, and the amount of substance.

Question 10

What is the equation of entropy?&#10;A)ratio of reversible transfer of heat to absolute temperature&#10;B)ratio of absolute temperature to reversible heat transfer&#10;C)ratio of adiabatic heat to macroscopic variables&#10;D)ratio of macroscopic variables to adiabatic heat

Accepted Answer

Entropy is defined as the ratio of the reversible transfer of heat to the absolute temperature at which the transfer takes place.

Question 11

SI unit of enthalpy is&#160;&#10;A)joule/kgk&#10;B)joule/k&#10;C)joule/kg&#10;D)k/kg

Accepted Answer

The answer of SI unit of enthalpy is&#160;&#10;A)joule/kgk&#10;B)joule/k&#10;C)joule/kg&#10;D)k/kg...

Question 12

Which among this is not an exothermic reaction?&#10;A)combustion reaction&#10;B)neutralization reaction&#10;C)thermite reaction&#10;D)evaporating liquid water

Accepted Answer

The answer of Which among this is not an exothermic...

Question 13

What reaction takes place during photosynthesis?&#10;A)exothermic reaction&#10;B)endothermic reaction&#10;C)redox reaction&#10;D)combustion reaction

Accepted Answer

The answer of What reaction takes place during photosynthesis?&#10;A)exothermic reaction&#10;B)endothermic...

Question 14

The first law of thermodynamics doesn't tell us whether a thermodynamic process is feasible or not.

Accepted Answer

The answer of The first law of thermodynamics doesn't tell...

Question 15

According to Joule's experiments,&#10;A)heat can be completely converted into work&#10;B)work can be completely converted into heat&#10;C)both heat and work are completely interchangeable&#10;D)all of the mentioned

Accepted Answer

The answer of According to Joule's experiments,&#10;A)heat can be completely...

Question 16

Which of the following is true?&#10;A)work is a high grade energy&#10;B)heat is a low grade energy&#10;C)complete conversion of low grade energy into high grade energy in a cycle is impossible&#10;D)all of the mentioned

Accepted Answer

The answer of Which of the following is true?&#10;A)work is...

Question 17

Boiler, turbine, condenser and pump together constitute a heat engine.

Accepted Answer

The answer of Boiler, turbine, condenser and pump together constitute...

Question 18

In a heat engine cycle, which of the following process occurs?&#10;A)heat is transferred from furnace to boiler&#10;B)work is produced in turbine rotor&#10;C)steam is condensed in condenser&#10;D)all of the mentioned

Accepted Answer

The answer of In a heat engine cycle, which of...

Question 19

A thermal energy reservoir is a large body of&#10;A)small heat capacity&#10;B)large heat capacity&#10;C)infinite heat capacity&#10;D)none of the mentioned

Accepted Answer

The answer of A thermal energy reservoir is a large...

Question 20

Processes inside a thermal energy reservoir are quasi-static.

Accepted Answer

The answer of Processes inside a thermal energy reservoir are...

Question 21

Carnot cycle is a reversible cycle.

Accepted Answer

The answer of Carnot cycle is a reversible cycle....

Question 22

Which if the following statements are true for a mechanical energy reservoir(MER)?&#10;A)it is a large body enclosed by an adiabatic impermeable wall&#10;B)stores work as ke or pe&#10;C)all processes within an mer are quasi- static&#10;D)all of the mentioned

Accepted Answer

The answer of Which if the following statements are true...

Question 23

The correct sequence of the processes taking place in a carnot cycle is&#10;A)adiabatic -> adiabatic -> isothermal -> isothermal&#10;B)adiabatic -> isothermal -> adiabatic -> isothermal&#10;C)isothermal -> isothermal -> adiabatic -> adiabatic&#10;D)isothermal -> adiabatic -> isothermal -> adiabatic

Accepted Answer

The answer of The correct sequence of the processes taking...

Question 24

Example of reversed heat engine is&#10;A)heat pump&#10;B)refrigerator&#10;C)both of the mentioned&#10;D)none of the mentioned

Accepted Answer

The answer of Example of reversed heat engine is&#10;A)heat pump&#10;B)refrigerator&#10;C)both...

Deck 12: Thermodynamics and Heat Transfer