A Carnot engine whose sink is at \(300~\text{K}\) has an efficiency of \(40\%.\) By how much should the temperature of the source be increased to increase its efficiency by \(50\%\) of its original efficiency?
1. \(275~\text{K}\) 2. \(325~\text{K}\)
3. \(250~\text{K}\) 4. \(380~\text{K}\)

Subtopic:  Carnot Engine |
 64%
Level 2: 60%+
AIPMT - 2006

To unlock all the explanations of this course, you need to be enrolled.

Hints
Links

To unlock all the explanations of this course, you need to be enrolled.


One mole of an ideal gas expands at a constant temperature of \(300~\text{K}\) from an initial volume of \(10\) litres to a final volume of \(20\) litres. The work done in expanding the gas is equal to:
(\(R = 8.31\) J/mole-K)
1. \(750~\text{J}\)
2. \(1728~\text{J}\)
3. \(1500~\text{J}\)
4. \(3456~\text{J}\)

Subtopic:  Work Done by a Gas |
 77%
Level 2: 60%+

To unlock all the explanations of this course, you need to be enrolled.

Hints

To unlock all the explanations of this course, you need to be enrolled.


premium feature crown icon
Unlock IMPORTANT QUESTION
This question was bookmarked by 5 NEET 2025 toppers during their NEETprep journey. Get Target Batch to see this question.
✨ Perfect for quick revision & accuracy boost
Buy Target Batch
Access all premium questions instantly

The pressure of a monoatomic gas increases linearly from \(4\times 10^5~\text{N/m}^2\) to \(8\times 10^5~\text{N/m}^2\) when its volume increases from \(0.2 ~\text m^3\) to \(0.5 ~\text m^3.\) The work done by the gas is:
1. \(2 . 8 \times10^{5}~\text J\)
2. \(1 . 8 \times10^{6}~\text J\)
3. \(1 . 8 \times10^{5}~\text J\)
4. \(1 . 8 \times10^{2}~\text J\)

Subtopic:  Work Done by a Gas |
 67%
Level 2: 60%+

To unlock all the explanations of this course, you need to be enrolled.

Hints

To unlock all the explanations of this course, you need to be enrolled.


advertisementadvertisement

A gas is taken through the cycle \(A\rightarrow B\rightarrow C\rightarrow A,\) as shown in the figure. What is the total amount of work done by the gas?
               
1. \(1000~\text{J}\) 2. zero
3. \(-2000~\text{J}\) 4. \(2000~\text{J}\)
Subtopic:  Work Done by a Gas |
 76%
Level 2: 60%+
AIPMT - 2013

To unlock all the explanations of this course, you need to be enrolled.

Hints
Links

To unlock all the explanations of this course, you need to be enrolled.


A thermodynamic system undergoes a cyclic process \(ABCDA\) as shown in Fig. The work done by the system in the cycle is: 

1. \( P_0 V_0 \) 2. \( 2 P_0 V_0 \)
3. \(\dfrac{P_0 V_0}{2} \) 4. zero
Subtopic:  Cyclic Process |
 83%
Level 1: 80%+
AIPMT - 2014

To unlock all the explanations of this course, you need to be enrolled.

Hints
Links

To unlock all the explanations of this course, you need to be enrolled.


A monoatomic gas at a pressure \(P\), having a volume \(V\), expands isothermally to a volume \(2V\) and then adiabatically to a volume \(16V\). The final pressure of the gas is: \(\left(\text{Take:}~ \gamma = \frac{5}{3} \right)\)
1. \(64P\) 2. \(32P\)
3. \(\frac{P}{64}\) 4. \(16P\)
Subtopic:  Types of Processes |
 76%
Level 2: 60%+
AIPMT - 2014

To unlock all the explanations of this course, you need to be enrolled.

Hints
Links

To unlock all the explanations of this course, you need to be enrolled.


advertisementadvertisement

A refrigerator works between 40C and 300C. It is required to remove 600 calories of heat every second to keep the temperature of the refrigerated space constant. The power required will be: 
(Take, 1 cal= 4.2 Joules)
1. 23.65 W
2. 236.5 W
3. 2365 W
4. 2.365 W
 73%
Level 2: 60%+
NEET - 2016

To unlock all the explanations of this course, you need to be enrolled.

Hints
Links

To unlock all the explanations of this course, you need to be enrolled.


premium feature crown icon
Unlock IMPORTANT QUESTION
This question was bookmarked by 5 NEET 2025 toppers during their NEETprep journey. Get Target Batch to see this question.
✨ Perfect for quick revision & accuracy boost
Buy Target Batch
Access all premium questions instantly

A horizontal cylinder has two sections of unequal cross-sections in which two pistons, A and B, can move freely. The pistons are joined by a string. Some gas is trapped between the pistons. If this gas is heated, the pistons will:  
         

1. move to the left.
2. move to the right.
3. remain stationary.
4. move either to the left or to the right depending on the initial pressure of the gas.

Subtopic:  First Law of Thermodynamics |
 53%
Level 3: 35%-60%

To unlock all the explanations of this course, you need to be enrolled.

Hints
Next Hint

To unlock all the explanations of this course, you need to be enrolled.


premium feature crown icon
Unlock IMPORTANT QUESTION
This question was bookmarked by 5 NEET 2025 toppers during their NEETprep journey. Get Target Batch to see this question.
✨ Perfect for quick revision & accuracy boost
Buy Target Batch
Access all premium questions instantly

In the \((P\text-V)\) diagram shown, the gas does \(5~\text J\) of work in the isothermal process \(ab\) and \(4~\text J\) in the adiabatic process \(bc.\) What will be the change in internal energy of the gas in the straight path from \(c\) to \(a?\) 

             
1. \(9~\text J\)
2. \(1~\text J\)
3. \(4~\text J\)
4. \(5~\text J\)

Subtopic:  Cyclic Process |
 58%
Level 3: 35%-60%

To unlock all the explanations of this course, you need to be enrolled.

Hints
Next Hint

To unlock all the explanations of this course, you need to be enrolled.


advertisementadvertisement

\(ABCA\) is a cyclic process. Its \(P\text-V\) graph would be:

           

1. 2.
3. 4.
Subtopic:  Cyclic Process |
 76%
Level 2: 60%+

To unlock all the explanations of this course, you need to be enrolled.

Hints

To unlock all the explanations of this course, you need to be enrolled.