Thermodynamics practice · Medium

In adiabatic process, the work done by system is $50 \mathrm{~J}$, then

A refrigerator consumes an average 35 W power to operate between temperature $10^\circ C$ to $25^\circ C$. If there is no loss of energy, then how much average heat per second does it transfer?

A bullet of mass $5\,g,$ travelling with a speed of $210\,\,m/s,\,$ strikes a fixed wooden target. One-half of its kinetic
energy is converted into heat in the bullet while the other half is converted into heat in the wood. The rise of
temperature of the bullet, if the specific heat of its material is $0.030\,\,\,\mathrm{cal }{g^{ - 1}}\,\,^\circ {C^{ - 1}}$ is close to

Assertion: Coefficient of performance in refrigerator may be greater than one.
Reason: Heat extracted from lower temperature reservoir.

A gaseous mixture enclosed in a vessel consists of $3 \mathrm{~g}$ mole of a gas $X$ with $\gamma=(5 / 3)$ and some amount of gas $Y$ with $\gamma=(7 / 5)$ at a temperature $T$. The gases $X$ and $Y$ do not react with each other and are assumed to be ideal. If $\gamma$ for the gaseous mixture is $\left(\frac{29}{23}\right)$, then the number of gram moles of the gas $Y$ is

Universal gas constant is

At $500 \mathrm{~K}$ for an isobaric process.

$\Delta \mathrm{S}_{\text {system }}=-10 \frac{\mathrm{kJ}}{\mathrm{mol} \mathrm{K}} \text { and } \Delta \mathrm{S}_{\text {surr }}=12 \frac{\mathrm{kJ}}{\mathrm{molK}}$

Therefore, $\Delta \mathrm{G}$ for the entire process is-

In an isobaric process, the absolute temperature is doubled. The mean free path $\left( \lambda \right)$ and the relaxation time $\left( \tau \right)$ will become respectively

A balloon filled with helium ($32^\circ C$ and 1.7 atm) bursts. Immediately afterwards; the expansion of helium can be considered as

The temperature of 5 moles of a gas at constant volume is changed from 100$^ \circ C$ to 120$^ \circ C$. The change in internal energy is 80 J. the total heat capacity of the gas at constant volume will be in $\mathrm{J}{\mathrm{K}^{ - 1}}$ is

Statement-1: The quantity of heat in a solid body determines its temperature.
Statement-2: Whenever heat is supplied to a solid body which is not undergoing phase change the temperature of the solid body increases.

A bullet of mass $10 \times 10^{-3} \mathrm{~kg}$ moving with a speed of $20 \mathrm{~ms}^{-1}$ hits an ice block $\left(0^{\circ} \mathrm{C}\right)$ of $990 \mathrm{~g}$ kept at rest on a frictionless floor and gets embedded in it. If ice takes $50 \%$ of KE lost by the system, the amount of ice melted (in grams) approximately is: $(J=4.2 \mathrm{~J} / \mathrm{cal}$; latent heat of ice $=80 \mathrm{~cal} / \mathrm{g}$)

A sample of ideal gas $(\gamma=1.4)$ is heated at constant pressure. If an amount $140 \mathrm{~J}$ of heat is supplied to the gas, find (a) the change in internal energy of the gas, (b) the work done by the gas.

The first operation involved in a carnot cycle is

If $C_p$ and $C_v$ are the specific heats for a gas at constant pressure and at constant volume respectively, then the relation $C_p-C_v=R$ is exact for

The heat capacity per mole of water is (R is universal gas constant)

$P_i, V_i$ and $P_f, V_f$ are initial and final pressures and volumes of a gas in a thermodynamic process respectively. If $P V^n=$ constant, then the amount of work done is

which of the following is the unit of specific heat

A system goes from $A$ and $B$ via two processes $I$ and $II$ as shown in figure. If $\Delta {U_1}$ and $\Delta {U_2}$ are the changes in internal energies in the process $I$ and $II$ respectively, then

The process in which no heat enters or leaves the system is termed as

Which of the following statements is correct for a thermodynamic gaseous system?

A Camot engine with efficiency 50% takes heat
from a source at 600 K. In order to increase the
efficiency to 70%, keeping the temperature of sink
same, the new temperature of the source will be:

The internal energy of the gas increases in

Assertion (A) : First law of thermodynamics can be applied for ideal gases only.

Reason (R) : First law is simply, law of conservation of energy.

When you make ice cubes, the entropy of water

In isothermal expansion, the pressure is determined by

$1\,m{m^3}$ of a gas is compressed at '$1$' atmospheric pressure and temperature ${27^0}C\,to\,{627^0}C$. What is the final pressure under adiabatic condition $\left( {\gamma for\,the\,gas = 1.5} \right)$

A Carnot engine takes heat from a reservoir at ${627^ \circ }C$ and rejects heat to a sink at ${27^ \circ }C$. Its efficiency will be

A perfect gas contained in a cylinder is kept in vacuum. If the cylinder suddenly bursts, then the temperature of the gas

During an adiabatic process, the pressure $p$ of a fixed mass of an ideal gas changes by $\Delta p$ and its volume $V$ changes $\Delta V$. If $\mathrm{\gamma } = {C_p}/{C_v}$ , then $\Delta V/V$ is given by