EASY

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A carnot engine has an efficiency of $30 %$ .Its efficiency is to be increased to $50 %$ .By what must the temperature of the source be increased if the sink is at $300 K$ ?

Important Questions on Thermodynamics

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

A Carnot engine of efficiency

40 %,

takes heat from a source maintained at a temperature of

500 K

. It is desired to have an engine of efficiency

60 %

. Then, the source temperature for the same sink temperature must be

EASY

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

Two carnot engines

A

and

B

are operated in series. The first one,

A,

receives heat at

T_{1} (= 600 K)

and rejects to a reservoir at temperature

T_{2} .

The second engine

B

receives heat rejected by the first engine and, in turn, rejects to a heat reservoir at

T_{3} (= 400 K) .

Calculate the temperature

T_{2}

if the work outputs of the two engines are equal:

EASY

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

The efficiency of carnot engine is

η

when its hot and cold reservoirs are maintained at temperature

T_{1}

and

T_{2}

, respectively. To increase the efficiency to

1.5 η

, the increase in temperature

(Δ T)

of the hot reservoir by keeping the cold one constant at

T_{2}

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

A carnot engine working between

200 K

and

500 K

has a work output of

900 J

per cycle. The amount of heat energy supplied to the engine from the source in each cycle is

HARD

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

Two ideal Carnot engines operate in a cascade (all heat given up by one engine is used by the other engine to produce work) between temperatures,

T_{1}

and

T_{2}

. The temperature of the hot reservoir of the first engine is

T_{1}

and the temperature of the cold reservoir of the second engine is

T_{2}

T

is the temperature of the sink of the first engine which is also the source for the second engine. How is

T

related to

T_{1}

and

T_{2}

, if both the engines perform an equal amount of work?

EASY

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

A Carnot engine takes

300

calories of heat from a source at

500 K

and rejects

150

calories of heat to the sink. The temperature of the sink is

EASY

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

Two carnot engines

A

and

B

are connected in series in such a way that the work outputs are equal when the temperatures of hot and cold reservoirs of

A

are

800 K

and

T

, and of engine

B

are

T

and

300 K

, respectively. Then the temperature

T

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

A Carnot engine whose low-temperature reservoir is at

350 K

has an efficiency of

50 %

. It is desired to increase this to

60 %

. If the temperature of the low-temperature reservoir remains constant, then the temperature of the high-temperature reservoir must be increased by how many degrees?

EASY

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

The efficiency of a Carnot engine depends upon

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

A reservoir is at

827 ° C

and Carnot's engine takes a thousand

kilo calorie

of heat from it and exhausts it to a sink at

27 ° C

. What is the amount of work and the efficiency of the engine?

HARD

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

An engine runs between a reservoir at temperature

200 K

and

a

hot body which is initially at temperature of

600 K .

If the hot body cools down to a temperature of

400 K

in the process, then the maximum amount of work that the engine can do (while working in a cycle) is (the heat capacity of the hot body is

1 J / K)

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

A Carnot engine has an efficiency of

\frac{1}{6} .

When the temperature of the sink is reduced by

62 ℃

, its efficiency is doubled. The temperatures of the source and the sink are, respectively,

EASY

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

For a Carnot engine which of the following is false?

EASY

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

The efficiency of Carnot engine is

0.6

. It rejects

20 J

of heat to sink. The work done by the engine is

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

A Carnot engine is operating between a hot body and cold body maintained at temperature $T_{1}$ and $T_{2}$ respectively. Consider the following three cases

Case I : The temperature of the hot body is changed to $T_{1} + Δ T$ and cold body is at $T_{2}$

Case II : The temperature of the hot body is at $T_{1}$ and cold body is changed to $T_{2} + Δ T$

Case III : The temperature of the hot body is

EASY

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

An ideal Carnot's engine works between

227 °

and

57 ° C

. Find the efficiency of the engine.

HARD

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

Two Carnot engines

A

and

B

operate in series such that engine A absorbs heat at

T_{1}

and rejects heat to a sink at temperature

T

. Engine

B

absorbs half of the heat rejected by Engine

A

and rejects heat to the sink at

T_{3}

. When workdone in both the cases is equal, to value of

T

is :

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

Helium gas goes through a cycle $A B C D A$ (consisting of two isochoric and two isobaric lines) as shown in figure. The efficiency of this cycle is approximately

Question Image

EASY

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

A Carnot engine having an efficiency of

\frac{1}{10}

is being used as a refrigerator. If the work done on the refrigerator is

10 J,

the amount of heat absorbed from the reservoir at a lower temperature is

MEDIUM

Physics>Heat and Thermodynamics>Thermodynamics>Carnot Engine

Three Carnot engines operate in series between a heat source at a temperature

T_{1}

and a heat sink at temperature

T_{4}

(see figure). There are two other reservoirs at temperature

T_{2}

and

T_{3},

as shown, with

T_{1} > T_{2} > T_{3} > T_{4} .

The three engines are equally efficient if:

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A carnot engine has an efficiency of 30%.Its efficiency is to be increased to 50%.By what must the temperature of the source be increased if the sink is at 300 K?

Important Questions on Thermodynamics

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A carnot engine has an efficiency of $30 %$ .Its efficiency is to be increased to $50 %$ .By what must the temperature of the source be increased if the sink is at $300 K$ ?