A gas is suddenly expanded such that its final volume becomes 3 times its initial volume. If the specific heat at constant volume of the gas is 2R, then the ratio of initial to final pressures is nearly equal to
1
5
2
6.5
3
7
4
3.5
Official Solution
Correct Option: (1)
Step 1: Concept
Sudden expansion implies an adiabatic process where . Step 2: Adiabatic Index
Given , then . . Step 3: Calculation
. Final Answer: (A)
02
PYQ 2010
medium
physicsID: met-2010
An ideal gas expands along the path AB as shown in the p-V diagram. The work done is
1
J
2
J
3
J
4
None of these
Official Solution
Correct Option: (2)
Step 1: Concept
Work done is equal to the area under the p-V curve. Step 2: Analysis
The area is a trapezium: . Step 3: Calculation
. Final Answer: (B)
