MCQOPTIONS
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MCQOPTIONS
This section includes 9 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering Physics knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
We consider a thermodynamic system. If U represents the increase in its internal energy and W, the work done by the system; which of the following statements are true? |
| A. | U=-W in an isothermal process |
| B. | U=W in an isothermal process |
| C. | U=-W in an adiabatic process |
| D. | U=W in an adiabatic process |
| Answer» D. U=W in an adiabatic process | |
| 2. |
Assertion: The temperature of a gas does not change, when it undergoes an adiabatic expansion.
|
| A. | Both assertion and reason are true and the reason is the correct explanation of the assertion |
| B. | Both assertion and reason are true but the reason is not a correct explanation of the assertion |
| C. | Assertion is true but the reason is false |
| D. | Both assertion and reason are false |
| Answer» E. | |
| 3. |
Even Carnot engine cannot give 100% efficiency, because we cannot ___________ |
| A. | Prevent radiation |
| B. | Find ideal sources |
| C. | Reach absolute zero temperature |
| D. | Eliminate friction |
| Answer» B. Find ideal sources | |
| 4. |
An ideal gas heat engine is operating between 227 C and 127 C. It absorbs 104 J of heat at the higher temperature. The amount of heat converted into work is? |
| A. | 2000 J |
| B. | 4000 J |
| C. | 8000 J |
| D. | 5600 J |
| Answer» B. 4000 J | |
| 5. |
A monoatomic ideal gas, initially at temperature T1 is enclosed in a cylinder fitted with a frictionless piston. The gas is allowed to expand adiabatically to a temperature T2 by releasing the piston suddenly. L1 and L2 are the lengths of the gas column before and after expansion respectively, then T1/T2 is given by? |
| A. | (L<sub>1</sub>/L<sub>2</sub>)<sup>(2/3)</sup> |
| B. | L<sub>1</sub>/L<sub>2</sub> |
| C. | L<sub>2</sub>/L<sub>1</sub> |
| D. | (L<sub>2</sub>/L<sub>1</sub>)<sup>(2/3)</sup> |
| Answer» E. | |
| 6. |
When a gas is suddenly compressed, its temperature decreases. |
| A. | True |
| B. | False |
| Answer» C. | |
| 7. |
An ideal gas is pressed at a constant temperature. Its internal energy ___________ |
| A. | Decreases |
| B. | Increases |
| C. | First increases and then decreases |
| D. | Remains the same |
| Answer» E. | |
| 8. |
A gas does work during isothermal expansion. The source of mechanical energy so produced is the internal energy of the gas itself. |
| A. | True |
| B. | False |
| Answer» C. | |
| 9. |
Any process in which the system returns to its initial state after undergoing a series of changes is known as ___________ |
| A. | Clockwise process |
| B. | Anticlockwise process |
| C. | Cyclic process |
| D. | Thermodynamic process |
| Answer» D. Thermodynamic process | |