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Initial pressure P₁ = P

Final pressure P₂ = P + \(\frac{0.4P}{100}\)

T₁ = T, T₂ = T + 1

At constant volume \(\frac{P_2}{P_1}\) = \(\frac{T_2}{T_1}\)

\(\frac{P(1+ 0.004)}{P}\) = \(\frac{T - 1}{T}\)

PT + 0.004 PT = PT + P

0.004PT = P

∴ T = \(\frac{1}{0.004}\) 

= 250 K

∴ Initial Temperature of the gas = 250 K

(c) convection 

Heat flows by the conventional current is upward direction by convection method.

\(\frac{ΔA}{A} =\)0.22% = \(= \frac {0.22}{100}\)

Change in temperature ΔT = 10°C

∴ Coefficient of cubical expansion

\(a_A = \frac{ΔA}{AΔT}\)

\(a_A = \frac{0.22}{100 \times 10} = 0.22 \times 10^{-3}\)

= 22 × 10 /°C

Correct answer is (c) More

(c) γ, α 

As γ is 3 times of α and β is 2 times of α. so α is minimum and γ is maximum.

(c) both (a) and (b) 

When a substance is heated its expansion is positive i,e, can be taken along either +X or +Y direction. But when substance is cooled it’s either length or area or volume decreases i.e. with respect expansion, it is opposite direction i.e. either -X or -Y direction respectively.

Correct answer is (c) Zero

The mass of a substance is constant according to the law of conservation of mass. It is independent of temperature change. Thus the change in the mass of a substance heated or cooled is zero.

No, This is because absolute zero on the kelvin scale is the minimum possible temperature.

When sugar is added to tea, its heat gets shared by sugar. So temperature of tea decreases.

1. It obeys all gas laws at all values of temperature pressure. 

2. Size of molecules is negligibly small. 

3. There is no force of attraction or repulsion between its molecule.

The relation between the different types of scale of temperature:

 Celsius and Kelvin:

K = C + 273

Fahrenheit and Kelvin: [K] = (F + 460) x \(\frac{5}{9}\)

0 K = -273 °C.

Ideal gas equation is also called as equation of state because it gives the relation between the state variables and it is used to describe the state of any gas.

The ideal gas equation is an equation, which relates all the properties of an ideal gas.

The process in which heat energy flows from a body at a higher temperature to another body at lower temperature is known as heating.

(b) sum of P.E and K.E

As the absolute temperature (T) is directly proportioned to KE of molecules of gas, and KE of molecules can never be negative so the absolute scale temperature can never be negative.

1. Temperature of the substance rises. 

2. The substance may change its state from solid to liquid or from liquid to gas. (Hi) The substance will expand when heated.

(a) Both the assertion and the reason are true and the reason is the correct explanation of the assertion.

It is because of the movement of electrons present in the materials.

1. 6.023 × 10²³ 

2. Inter convertible 

3. 1 gram, 1°C 

4. A straight line

1. True 

2. False -The relation between Celsius and Kelvin is K= C + 273 

3. True 

4. False – When a body is heated mass is not altered. 

5. True 

6. True 

7. False – Cubical expansion is different for different materials. 

8. True 

9. False – As per Boyle’s law PV= constant. 

10. True

\(\frac{ΔA}{A_0}\) = \(a_AΔT\)

ΔA – Change in area (Final area – Initial area) 

A₀ – Original area 

ΔT – Change in temperature (Final temperature – Initial temperature) 

α_A – Coefficient of superficial expansion.

Coefficient of apparent expansion is defined as the ratio of the apparent rise in the volume of the liquid per degree rise in temperature to its unit volume. 

The SI unit of the coefficient of apparent expansion is K^-1

\(\frac{ΔV}{V_0}\) = \(a_AΔT\)

ΔV - change in volume (final volume - initial volume)

V₀ – Original volume

ΔT – Change in temperature (Final temperature – Initial temperature )

\(a_V\) – Coefficient of cubical expansion.

Coefficient of real expansion is defined as the ratio of the true rise in the volume of the liquid per degree rise in temperature to its unit volume. The SI unit of coefficient of real expansion is the K^-1.

If a liquid is heated directly without using any container, then the expansion that you observe is termed as real expansion of the liquid.

(d) perfect gas

(b) Pv = nRT

T represents absolute temperature by t temperature in 0°C.

Correct answer is (c) PV = RT

(d) PV = constant

(d) PV = constant

Correct answer is (b) V ∝ n

(c) \(\frac{V}{T}\) = constant

Correct answer is (b) 8.31 J/mol/K

Correct answer is (b) Ideal gas

(c) Avogadro's law

A – (t) 

B – (s) 

C – (p) 

D – (q)

1. True 

2. True

3. False – According to Charles law, at constant pressure, the volume is directly proportional to temperature.

When the temperature of a gas is kept constant, the volume of a fixed mass of gas is inversely proportional to its pressure.

P ∝ 1 / V

The ratio of increase in the volume of the body per degree rise in temperature to its unit volume is called a coefficient of cubical expansion.

A. (s)

B. (t) 

C. (p) 

D. (q) 

E. (r)

A body appears hot when touched if heat flows from the body to our hand and vice – versa. If there is no flow of heat across the body and hand, the body can not be identified while it is hot or cold as bodies are in thermal equilibrium with our body. So both block of wood and metal must have the temperature of our body i.e., 37°C.

Some thermal energy is transferred from the hot body to the cold body. As a result, there is some rise in the temperature of the cold body and decrease in the temperature of the hot body. This process will continue until these two bodies attain the same temperature.

There will be a transfer of heat energy from the hot body to the cold body until a thermal equilibrium is established between them.

When the pressure of a gas  is kept constant,, the volume of a gas is directly proportional to the temperature of the gas.

i.e., V ∝ T.

(or)

\(\frac{V}{T}\) = constant

As the thermal (cubical) expansion of gas is much larger than Hg. So gas thermometer is more sensitive than of Hg thermometer.

(c) The assertion is true but the reason is false.