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Pressure versus temperature graph for an ideal gas is as shown in the figure. Corresponding density $(ρ)$ versus volume $(v)$ graph will be

Important Questions on Thermal Properties of Matter

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Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

An ideal gas filled in a cylinder occupies volume,

V

. The gas is compressed isothermally to the volume,

\frac{V}{3}

. Now the cylinder valve is opened and the gas is allowed to leak keeping the temperature the same. What percentage of the number of molecules escape to bring the pressure in the cylinder back to its original value.

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Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

A vertical closed cylinder is separated into two parts by a frictionless piston of mass

m

and of negligible thickness. The piston is free to move along the length of the cylinder. The length of the cylinder above piston is

l_{1},

and that below the piston is

l_{2},

such that

l_{1} > l_{2} .

Each part of the cylinder contains

n

moles of an ideal gas at equal temperature

T .

If the piston is stationary, its mass

m

will be given by:
(

R

is universal gas constant and

g

is the acceleration due to gravity)

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

The temperature of an open room of volume

30 m^{3}

increases from

17 ° C

27 ° C

due to the sunshine. The atmospheric pressure in the room remains

1 \times 10^{5} Pa

. If

n_{i}

and

n_{f}

are the number of molecules in the room before and after heating, then

n_{f} - n_{i}

will be:

HARD

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

A long cylindrical pipe of radius $20 cm$ is closed at its upper end and has an airtight piston of negligible mass as shown. When $a$ $50 kg$ mass is attached to the other end of piston, it moves down by a distance, $Δ l$ before coming to equilibrium. Assuming air to be an ideal gas, $\frac{Δ l}{l}$ (see figure) is close to $(g = 10 m s^{- 2}$ , one atmospheric pressure is $10^{5} Pa$ ),

Question Image

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

Mercury is often used in clinical thermometers. Which one of the following properties of mercury is not a reason for this?

HARD

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

Two non-reactive monoatomic ideal gases have their atomic masses in the ratio 2 : 3. The ratio of their partial pressures, when enclosed in a vessel kept at a constant temperature, is 4 : 3. The ratio of their densities is

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

A given sample of an ideal gas occupies a volume,

V

at a pressure,

P

and absolute temperature,

T

. The mass of each molecule of the gas is

m

. Which of the following gives the density of the gas?

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

The state of an ideal gas was changed isobarically. The graph depicts three such isobaric lines. Which of the following is true about the pressures of the gas?
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HARD

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

A certain liquid has a melting point of

- 50 ° C

and a boiling point of

150 ° C

. A thermometer is designed with this liquid and its melting and boiling points are designated at

0 ° L

and

100 ° L

. The melting and boiling points of water on this scale are

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

The SI unit of mechanical equivalent of heat is

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

For the

P - V

diagram given for an ideal gas
Question Image

Out of the following which one correctly represents the

T - P

diagram?

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Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

A thin paper cup filled with water does not catch fire when placed over a flame. This is because

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Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

The average distance between molecules of an ideal gas at STP is approximately of the order of

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

A cylinder closed at both ends is separated into two equal parts (

45 cm

each) by a piston impermeable to heat. Both the parts contain the same masses of gas at a temperature of

300 K

and a pressure of

1 atm

. If now the gas in one of the parts is heated such that the piston shifts by

5 cm

, then the temperature and the pressure of the gas in this part after heating is

MEDIUM

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

An ideal gas undergoes a circular cycle centred at $4 atm$ , $4 L$ as shown in the diagram.

Question Image

The maximum temperature attained in this process is close to

HARD

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

An open glass tube is immersed in mercury in such a way that a length of

8 cm

extends above the mercury level. The open end of the tube is then closed and sealed and the tube is raised vertically up by additional

46 cm

. What will be length of the air column above mercury in the tube now ?
(Atmospheric pressure =

76 cm

of Hg)

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

Modern vacuum pumps can evacuate a vessel down to a pressure of

4.0 \times 1 0^{- 15}

atm. at room temperature (300 K). Taking R = 8.3 JK^-1 mole^-1, 1 atm = 10⁵ Pa and

N_{Avogadro} = 6 \times 1 0^{23} {mole}^{- 1}

, the mean distance between molecules of gas in an evacuated vessel will be of the order of :

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

Pyrometer is a device for measuring

EASY

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

Ice is used in a cooler in order to cool its contents. Which of the following will speed up the cooling process?

MEDIUM

Physics>Heat and Thermodynamics>Thermal Properties of Matter>Measurement of Temperature

Solar energy is incident normally on the earth's surface at the rate of about

1 .4 kW m^{- 2}

. The distance between the earth and the sun is

1 .5 \times 10^{11} m

. Energy

(E)

and mass

(m)

are related by the Einstein equation,

E = m c^{2}

where

c = (3 \times 10^{8} m s^{- 1})

is the speed of light in free space. The decrease in the mass of the sun is

Pressure versus temperature graph for an ideal gas is as shown in the figure. Corresponding density (ρ) versus volume (v) graph will be

Important Questions on Thermal Properties of Matter

Learn and Prepare for any exam you want !

Pressure versus temperature graph for an ideal gas is as shown in the figure. Corresponding density $(ρ)$ versus volume $(v)$ graph will be