Home
Class 11
PHYSICS
Two different ideal diatomic gases A and...

Two different ideal diatomic gases `A` and `B` are initially in the same state. `A` and `B` are then expanded to same final volume through adiabatic and isothermal process respectively. If `P_(A), P_(B)` and `T_(A), T_(B)` represents the final pressure and temperature of `A` and `B` respectively then.

A

`P_(A) lt P_(B)` and `T_(A) lt T_(B)`

B

`P_(A) gt P_(B)` and `T_(A) gt T_(B)`

C

`P_(A) gt P_(B)` and `T_(A) lt t_(B)`

D

`P_(A) lt P_(B)` and `T_(A) gt T_(B)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we will analyze the behavior of two different ideal diatomic gases, A and B, during their respective processes: an adiabatic expansion for gas A and an isothermal expansion for gas B. We will derive the relationships between their final pressures and temperatures. ### Step-by-Step Solution: 1. **Understanding the Processes**: - Gas A undergoes an **adiabatic expansion**, meaning there is no heat exchange with the surroundings. The internal energy change results in a change in temperature and pressure. - Gas B undergoes an **isothermal expansion**, where the temperature remains constant throughout the process. The gas absorbs heat from the surroundings to maintain constant temperature while expanding. 2. **Final State**: - Both gases are expanded to the **same final volume**. Let’s denote this final volume as \( V_f \). 3. **Using the Ideal Gas Law**: - For both gases, we can use the ideal gas law, which states: \[ PV = nRT \] - Rearranging gives us: \[ P = \frac{nRT}{V} \] - Since both gases have the same number of moles \( n \) and the same final volume \( V_f \), we can express their pressures in terms of their temperatures: \[ P_A = \frac{nRT_A}{V_f} \quad \text{(for gas A)} \] \[ P_B = \frac{nRT_B}{V_f} \quad \text{(for gas B)} \] 4. **Analyzing the Adiabatic Process (Gas A)**: - In an adiabatic process for an ideal gas, the relationship between pressure and temperature can be expressed as: \[ P_A V_f^{\gamma} = \text{constant} \] - Here, \( \gamma \) (gamma) is the heat capacity ratio \( C_p/C_v \). As gas A expands adiabatically, its temperature decreases, leading to a lower final pressure \( P_A \). 5. **Analyzing the Isothermal Process (Gas B)**: - In the isothermal process, the temperature remains constant. Thus, the pressure can be expressed as: \[ P_B = \frac{nRT_B}{V_f} \] - Since \( T_B \) remains constant and is generally higher than \( T_A \) (due to the heat absorbed), the final pressure \( P_B \) will be higher than \( P_A \). 6. **Comparing Pressures**: - From the analysis, we can conclude: \[ P_B > P_A \] 7. **Comparing Temperatures**: - Since \( P \) is directly proportional to \( T \) when \( V \) is constant, we can also conclude: \[ T_B > T_A \] ### Final Relationships: - Therefore, we have: \[ P_B > P_A \quad \text{and} \quad T_B > T_A \] ### Conclusion: The final results indicate that the pressure of gas B (isothermal process) is greater than the pressure of gas A (adiabatic process), and the temperature of gas B is also greater than that of gas A. ---

To solve the problem, we will analyze the behavior of two different ideal diatomic gases, A and B, during their respective processes: an adiabatic expansion for gas A and an isothermal expansion for gas B. We will derive the relationships between their final pressures and temperatures. ### Step-by-Step Solution: 1. **Understanding the Processes**: - Gas A undergoes an **adiabatic expansion**, meaning there is no heat exchange with the surroundings. The internal energy change results in a change in temperature and pressure. - Gas B undergoes an **isothermal expansion**, where the temperature remains constant throughout the process. The gas absorbs heat from the surroundings to maintain constant temperature while expanding. ...
Promotional Banner

Topper's Solved these Questions

  • KTG & THERMODYNAMICS

    RESONANCE ENGLISH|Exercise PART -III|25 Videos
  • KTG & THERMODYNAMICS

    RESONANCE ENGLISH|Exercise PART -IV|9 Videos
  • KTG & THERMODYNAMICS

    RESONANCE ENGLISH|Exercise Exercise-2|1 Videos
  • KINETIC THEORY OF GASES AND THERMODYNAMICS

    RESONANCE ENGLISH|Exercise Exercise|64 Videos
  • MAGNETIC FIELD AND FORCES

    RESONANCE ENGLISH|Exercise Exercise|64 Videos