Question

The figure shows three paths traversed by a gas on P-V diagram. Let U1 , U2 and U3 are the changes in internal energy of the gas, then
(1) U1 > U2 > U3
(2)​ U3 > U2 > U1
​ (3) U1 = U2 = U3
(4)​ U3 > U2 = U1

Answer 1

Answer:

Here the three paths are ADB , AB , ACB Work done in ADB = WAD + WDB = 10 × 15 × 10-3 + 0 = 0.15 J Work done in AB = Area under AB and V - axis = 12

Answer 2

Given:

The figure shows three paths traversed by a gas on P-V diagram. Let U1 , U2 and U3 are the changes in internal energy of the gas.

To find:

Relation between the internal energy change in the three processes.

Calculation:

For a gas , the internal energy change in any process be U .

$\boxed{ \sf{U = n \times C_{v} \times \Delta T }}$

n is the number of moles , C_(v) is the molar heat capacity and ∆T is the change in temperature.

For constant n and C_(v) :

$\boxed{ \sf{U \: \propto \: \Delta T }}$

Temperature change is equal in process 1 and 2.

Also , temperature change is maximum in 3.

So, final answer is :

$\boxed{ \bold{ \large{U3 > U2 = U1}}}$