Two Carnot engines A and B are operated in succession. The first one, A receives heat from a source at T1 = 800 K and rejects to sink at T2 K. The second engine B receives heat rejected by the first engine and rejects to another sink at T3 = 300 K. If the work outputs of two engines are equal, then the value of T2 is -

(1) 100K

(2) 300K

(3) 550K

(4) 700K

Concept Questions :-

Heat engine and refrigerator
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Difficulty Level:

When an ideal monoatomic gas is heated at constant pressure, fraction of heat energy supplied which increases the internal energy of gas, is

(1) $\frac{2}{5}$

(2) $\frac{3}{5}$

(3) $\frac{3}{7}$

(4) $\frac{3}{4}$

Concept Questions :-

Molar Specific heat
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

When an ideal gas (γ = 5/3) is heated under constant pressure, then what percentage of given heat energy will be utilised in doing external work ?

(1) 40 %

(2) 30 %

(3) 60 %

(4) 20 %

Concept Questions :-

Molar Specific heat
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

Which one of the following gases possesses the largest internal energy?

(1) 2 moles of helium occupying 1m3 at 300 K

(2) 56 kg of nitrogen at  ${10}^{5}$ Nm–2 and 300 K

(3) 8 grams of oxygen at 8 atm and 300 K

(4) 6 × 1026 molecules of argon occupying 40 m3 at 900 K

Concept Questions :-

Basic terms
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Difficulty Level:

Two samples A and B of a gas initially at the same pressure and temperature are compressed from volume V to V/2 (A isothermally and B adiabatically). The final pressure of A is

(1) Greater than the final pressure of B

(2) Equal to the final pressure of B

(3) Less than the final pressure of B

(4) Twice the final pressure of B

Concept Questions :-

Types of processes
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Difficulty Level:

Initial pressure and volume of a gas are P and V respectively. First it is expanded isothermally to volume 4V and then compressed adiabatically to volume V. The final pressure of gas will be [Given : -

(1) 1P

(2) 2P

(3) 4P

(4) 8P

Concept Questions :-

Types of processes
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Difficulty Level:

A thermally insulated rigid container contains an ideal gas heated by a filament of resistance 100 Ω through a current of 1A for 5 min . Then change in internal energy is -

(1) 0 kJ

(2) 10 kJ

(3) 20 kJ

(4) 30 kJ

Concept Questions :-

First law of thermodynamics
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

A reversible engine converts one-sixth of the heat input into work. When the temperature of the sink is reduced by 62°C, the efficiency of the engine is doubled. The temperatures of the source and sink are -

(1) 80°C, 37°C

(2) 95°C, 28°C

(3) 90°C, 37°C

(4) 99°C, 37°C

Concept Questions :-

Heat engine and refrigerator
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

An ideal gas expands in such a manner that its pressure and volume can be related by equation . During this process, the gas is

(1) Heated

(2) Cooled

(3) Neither heated nor cooled

(4) First heated and then cooled

High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:

P-V diagram of a diatomic gas is a straight line passing through origin. The molar heat capacity of the gas in the process will be -

(1) 4 R

(2) 2.5 R

(3) 3 R

(4) $\frac{4R}{3}$

Concept Questions :-

Molar Specific heat