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In a gaseous system, a gas expands from ...

In a gaseous system, a gas expands from `10^(-4)m^3` to `2xx10^(-4)m^3` while itspressure remains constant at `10^(-4) Nt//m^2`. Calculate the amount of heat absorbed by the gas inthe expansion. `[gamma=1.67]`

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To solve the problem, we will follow these steps: ### Step 1: Identify the parameters Given: - Initial volume, \( V_i = 10^{-4} \, m^3 \) - Final volume, \( V_f = 2 \times 10^{-4} \, m^3 \) - Constant pressure, \( P = 10^{-4} \, N/m^2 \) - \( \gamma = 1.67 \) ### Step 2: Calculate the work done during expansion For an isobaric process (constant pressure), the work done \( W \) is given by the formula: \[ W = P \Delta V \] where \( \Delta V = V_f - V_i \). Calculating \( \Delta V \): \[ \Delta V = V_f - V_i = 2 \times 10^{-4} - 10^{-4} = 10^{-4} \, m^3 \] Now substituting the values into the work done formula: \[ W = P \Delta V = 10^{-4} \, N/m^2 \times 10^{-4} \, m^3 = 10^{-8} \, J \] ### Step 3: Calculate the change in internal energy \( \Delta U \) The change in internal energy for an ideal gas can be calculated using the formula: \[ \Delta U = n C_V \Delta T \] where \( C_V \) can be expressed in terms of \( R \) and \( \gamma \): \[ C_V = \frac{R}{\gamma - 1} \] Using the ideal gas law \( PV = nRT \), we can find the change in temperature \( \Delta T \): From the initial and final states: \[ P V_i = n R T_i \quad \text{(1)} \] \[ P V_f = n R T_f \quad \text{(2)} \] Subtracting (1) from (2): \[ P (V_f - V_i) = n R (T_f - T_i) \] This gives us: \[ \Delta T = \frac{P (V_f - V_i)}{n R} \] Substituting \( W \) for \( P (V_f - V_i) \): \[ \Delta T = \frac{W}{n R} \] Substituting \( W = 10^{-8} \, J \): \[ \Delta T = \frac{10^{-8}}{n R} \] Now substituting \( \Delta T \) back into the internal energy equation: \[ \Delta U = n \left(\frac{R}{\gamma - 1}\right) \left(\frac{10^{-8}}{n R}\right) \] This simplifies to: \[ \Delta U = \frac{10^{-8}}{\gamma - 1} \] Substituting \( \gamma = 1.67 \): \[ \Delta U = \frac{10^{-8}}{1.67 - 1} = \frac{10^{-8}}{0.67} \approx 1.492 \times 10^{-8} \, J \] ### Step 4: Calculate the total heat absorbed \( Q \) Using the first law of thermodynamics: \[ Q = \Delta U + W \] Substituting the values: \[ Q = 1.492 \times 10^{-8} + 10^{-8} = 2.492 \times 10^{-8} \, J \] ### Final Answer The amount of heat absorbed by the gas during the expansion is: \[ Q \approx 2.492 \times 10^{-8} \, J \] ---
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