An ideal monoatomic gas is confined in a horizontal cylinder by a spring loaded piston (as shown in the figure). Initially the gas is at temperature $T _1$, pressure $P_1$ and volume $V_1$ and the spring is in its relaxed state. The gas is then heated very slowly to temperature $T_2$, pressure $P _2$ and volume $V _2$. During this process the piston moves out by a distance $x$. Ignoring the friction between the piston and the cylinder, the correct statement$(s)$ is(are)

$(A)$ If $V_2=2 V_1$ and $T_2=3 T_1$, then the energy stored in the spring is $\frac{1}{4} P_1 V_1$

$(B)$ If $V_2=2 V_1$ and $T_2=3 T_1$, then the change in internal energy is $3 P_1 V_1$

$(C)$ If $V_2=3 V_1$ and $T_2=4 T_1$, then the work done by the gas is $\frac{7}{3} P_1 V_1$

$(D)$ If $V_2=3 V_1$ and $T_2=4 T_1$, then the heat supplied to the gas is $\frac{17}{6} P_1 V_1$

IIT 2015, Medium
Download our app for free and get startedPlay store
$P \text { (pressure of gas) }=P_1+\frac{k x}{A}$

$W =\int PdV = P _1\left( V _2- V _1\right)+\frac{ kx ^2}{2}= P _1\left( V _2- V _1\right)+\frac{\left( P _2- P _1\right)\left( V _2- V _1\right)}{2}$

$\Delta U = nC _{ V } \Delta T =\frac{3}{2}\left( P _2 V _2- P _1 V _1\right)$

$Q = W +\Delta U$

$\text { Case I: } \Delta U =3 P _1 V _1, W =\frac{5 P _1 V _1}{4}, Q =\frac{17 P _1 V _1}{4}, U _{\text {spring }}=\frac{ P _1 V _1}{4} $

$\text { Case II: } \Delta U =\frac{9 P _1 V _1}{2}, W =\frac{7 P _1 V _1}{3}, Q =\frac{41 P _1 V _1}{6}, U _{\text {spring }}=\frac{ P _1 V _1}{3}$

art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    During an experiment, an ideal gas is found to obey a condition $\frac{{{P^2}}}{\rho }$ = constant [$\rho =$ density of the gas]. The gas is initially at temperature $T,$ pressure $P$ and density $\rho$ . The gas expands such that density changes to $\rho/2$
    View Solution
  • 2
    A cyclic process of a thermodynamic system is taken through $a$ $b$ $c$ $d$ $a$. The work done by the gas along the path $b$ $c$ is
    View Solution
  • 3
    A cyclic process $ABCD$ is shown in the $p-V$ diagram. Which of the following curves represents the same process if $BC \& DA$ are isothermal processes
    View Solution
  • 4
    In the diagrams $(i)$ to $(iv)$ of variation of volume with changing pressure is shown. A gas is taken along the path $ABCD. $ The change in internal energy of the gas will be
    View Solution
  • 5
    A vertical cylinder with heat-conducting walls is closed at the bottom and is fitted with a smooth light piston. It contains one mole of an ideal gas. The temperature of the gas is always equal to the surrounding’s temperature, $T_0$. The piston is moved up slowly to increase the volume of the gas to $\eta$ times. Which of the following is incorrect?
    View Solution
  • 6
    Neon gas of a given mass expands isothermally to double volume. What should be the further fractional decrease in pressure, so that the gas when adiabatically compressed from that state, reaches the original state?
    View Solution
  • 7
    A certain mass of gas at $273 K$ is expanded to $81$ times its volume under adiabatic condition. If $\gamma = 1.25$ for the gas, then its final temperature is ..... $^oC$
    View Solution
  • 8
    An enclosed ideal gas is taken through a cycle as shown in the figure. Then
    View Solution
  • 9
    A Carnot engine operates between ${227^o}C$ and ${27^o}C.$ Efficiency of the engine will be
    View Solution
  • 10
    A Carnot's engine working between $400\, K$ and $800\, K$ has a work output of $1200\, J$ per cycle. The amount of heat energy supplied to the engine from the source in each cycle is ........... $J$
    View Solution