HARD

Earn 100

The figure shows the p-V plot an ideal gas taken through a cycle ABCDA. The part ABC is a semi - circle and CDA is half of an ellipse. Then,

50% studentsanswered this correctly

Important Questions on Thermodynamics

EASY

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

A thermodynamics system undergoes cyclic process

A B C D A

as shown in Figure. The work done by the system in the cycle is:
Question Image

EASY

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

One mole of a monoatomic ideal gas expanded by a process described by

P V^{3} = C

where

C

is a constant. The heat capacity of the gas during the process is given by (

R

is the gas constant)

HARD

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

One mole of a monoatomic ideal gas goes through a thermodynamic cycle, as shown in the volume versus temperature

(V - T)

diagram. The correct statement(s) is/are:

[

R

is the gas constant]
Question Image

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

An ideal gas undergoes the cyclic process

a b c a

as shown in the given

p - V

diagram.

It rejects

50 J

of heat during

a b

and absorbs

80 J

of heat during

c a

. During

b c

, there is no transfer of heat and

40 J

of work is done by the gas. What should be the area of the closed curve

a b c a ?

HARD

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

A gas obeying the equation of state

P V = R T

undergoes a hypothetical reversible process described by the equation,

P V^{\frac{5}{3}} \exp (- \frac{P V}{E_{0}}) = C_{1}

, where

C_{1}

and

E_{0}

are dimensioned constants. Then, for this process, the thermal compressibility at high temperature

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

Which of the following is an equivalent cyclic process corresponding to the thermodynamic cyclic given in the figure? Where,

1 \to 2

is adiabatic. (Graphs are schematic and are not to scale)
Question Image

HARD

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

An ideal gas undergoes a quasi-static, reversible process in which its molar heat capacity C remains constant. If during this process the relation of pressure P and volume V is given by

P V^{n} =

constant, then n is given by (Here

C_{P}

and

C_{V}

are molar specific heat at constant pressure and constant volume, respectively) :

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

In a certain thermodynamical process, the pressure of a gas depends on its volume as

k V^{3}

. The work done when the temperature changes from

100 ° C

300 ° C

will be

x n R

, where

n

denotes number of moles of a gas find

x

;

HARD

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

One mole of an ideal monatomic gas is taken along the path

A B C A

as shown in the

P - V

diagram. The maximum temperature attained by the gas along the path

B C

is given by:
Question Image

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

One mole of an ideal monatomic gas undergoes a process described by the equation

P V^{3} =

constant. The heat capacity of the gas during this process is

HARD

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

For an ideal gas, the internal energy is given by

U = 5 p V / 2 + C,

where

C

is a constant. The equation of the adiabats in the

p V

-plane will be

EASY

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

For the given cyclic process $C A B$ as shown for a gas, the work done is:

Question Image

EASY

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

$n$ mole of a perfect gas undergoes a cyclic process $A B C A$ (see figure) consisting of the following processes.

$A \to B :$ Isothermal expansion at temperature $T$ so that the volume is doubled from $V_{1}$ to $V_{2} = 2 V_{1}$ and pressure changes from $P_{1}$ to $P_{2}$
$B \to C :$ Isobaric compression at pressure $P_{2}$ to initial volume $V_{1} .$

$C \to A :$ Isochoric change leading to change of pressure from $P_{2}$ to $P_{1}$

Total work done in the complete cycle $A B C A$ is:

Question Image

HARD

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

A thermodynamic cycle

x y z x

is shown on a

V

T

diagram.

The

P

V

diagram that best describes this cycle is: (Diagrams are schematic and not to scale)

HARD

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

If one mole of an ideal gas at $(P_{1}, V_{1})$ is allowed to expand reversibly and isothermally ( $A$ to $B$ ) its pressure is reduced to one-half of the original pressure (see figure). This is followed by a constant volume cooling till its pressure is reduced to one-fourth of the initial value $(B \to C) .$ Then it is restored to its initial state by a reversible adiabatic compression ( $C$ to $A$ ). The net workdone by the gas is equal to:

Question Image

HARD

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

One mole of an ideal gas is taken around the complete cycle as shown in the PV-diagram. Considering the universal gas constant R, the work done by the gas in one complete cycle is:

Question Image

EASY

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

The heat energy absorbed by a system is going through a cyclic process shown in the figure. The work done during the process is

Question Image

HARD

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

An engine operates by taking

n

moles of an ideal gas through the cycle

A B C D A

shown in figure. The thermal efficiency of the engine is:

(Take

C_{v} = 1.5 R

, where

R

is gas constant)

Question Image

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

An ideal gas goes through a reversible cycle

a \to b \to c \to d

has the V - T diagram shown below. Process

d \to a a n d b \to c

are adiabatic.

Question Image

The corresponding P - V diagram for the process is (all figures are schematic and not drawn to scale) :

HARD

Physics>Heat and Thermodynamics>Thermodynamics>First Law of Thermodynamics

One mole of a monatomic ideal gas undergoes a cyclic process as shown in the figure (where V is the volume and T is the temperature). Which of the statements below is (are) true?

Question Image

The figure shows the p-V plot an ideal gas taken through a cycle ABCDA. The part ABC is a semi - circle and CDA is half of an ellipse. Then,

Important Questions on Thermodynamics

Learn and Prepare for any exam you want !