Grade 11 : Physics - Thermal Properties (Set 6)

Question 1

The Zeroth Law of Thermodynamics forms the theoretical basis for defining which fundamental physical quantity?

Accepted Answer

B) Temperature

Answer

A) Internal Energy

Answer

C) Heat Capacity

Answer

D) Entropy

Question 2

For an isotropic solid material, what is the exact numerical ratio between the coefficients of linear ($ \alpha$), superficial ($ \beta$), and volumetric ($ \gamma$) expansion?

Accepted Answer

A) $1 : 2 : 3$

Answer

B) $1 : 3 : 2$

Answer

C) $3 : 2 : 1$

Answer

D) $1 : 1 : 1$

Question 3

What is the equivalent temperature in Kelvin ($ K$) corresponding to $25°C$?

Accepted Answer

B) 298.15 K

Answer

A) 248.15 K

Answer

C) 318.15 K

Answer

D) 273.15 K

Question 4

Water exhibits anomalous thermal expansion when heated within which specific temperature interval?

Accepted Answer

A) $0^\circ	ext{C}$ to $4^\circ	ext{C}$

Answer

B) $4^\circ	ext{C}$ to $100^\circ	ext{C}$

Answer

C) $-4^\circ	ext{C}$ to $0^\circ	ext{C}$

Answer

D) $4^\circ	ext{C}$ to $8^\circ	ext{C}$

Question 5

Which basic mathematical equation gives the heat energy $Q$ required to change the temperature of a body of mass $m$ and specific heat capacity $c$ by $ \Delta T$?

Accepted Answer

A) $Q = m c \Delta T$

Answer

B) $Q = \frac{m c}{\Delta T}$

Answer

C) $Q = \frac{m \Delta T}{c}$

Answer

D) $Q = m c^2 \Delta T$

Question 6

The specific latent heat of fusion ($L_f$) represents the heat energy absorbed per unit mass during which phase change?

Accepted Answer

B) Solid to liquid at constant temperature

Answer

A) Liquid to gas at constant temperature

Answer

C) Solid directly to gas at constant temperature

Answer

D) Liquid to solid with changing temperature

Question 7

What is the standard SI unit for thermal conductivity ($k$)?

Accepted Answer

A) $	ext{W}\cdotm^{-1}\cdot	ext{K}^{-1}$

Answer

B) $	ext{J}\cdotm\cdot	ext{K}^{-1}$

Answer

C) $	ext{W}\cdotm\cdot	ext{K}$

Answer

D) $	ext{J}\cdot	ext{s}^{-1}\cdot	ext{K}^{-1}$

Question 8

According to Wien's Displacement Law, what is the relation between peak emission wavelength $ \lambda_{max}and absolute temperatureT$ of a blackbody?

Accepted Answer

A) $\lambda_{	ext{max}} T = b$ (constant)

Answer

B) $\frac{\lambda_{	ext{max}}}{T} = b$ (constant)

Answer

C) $\lambda_{	ext{max}} T^2 = b$ (constant)

Answer

D) $\lambda_{	ext{max}} \sqrt{T} = b$ (constant)

Question 9

The rate of conductive heat transfer $ \frac{Q}{t}across a uniform rod of lengthL$ and cross-sectional area $Awith temperature difference \Delta T$ is given by:

Accepted Answer

A) $\frac{Q}{t} = \frac{k A \Delta T}{L}$

Answer

B) $\frac{Q}{t} = \frac{k L \Delta T}{A}$

Answer

C) $\frac{Q}{t} = k A L \Delta T$

Answer

D) $\frac{Q}{t} = \frac{k}{A L \Delta T}$

Question 10

According to Dulong and Petit's Law, the molar specific heat capacity of most simple elemental solids at room temperature is approximately equal to:

Accepted Answer

C) $3R$

Answer

A) $R$

Answer

B) $2R$

Answer

D) $\frac{3}{2}R$

Question 11

If a metal rod of Young's modulus $Y$ and linear expansion coefficient $ \alphais held firmly between rigid walls and heated by \Delta T, the developed thermal stress \sigma$ is:

Accepted Answer

A) $\sigma = Y \alpha \Delta T$

Answer

B) $\sigma = \frac{Y}{\alpha \Delta T}$

Answer

C) $\sigma = Y \alpha^2 \Delta T$

Answer

D) $\sigma = \frac{Y \alpha}{\Delta T}$

Question 12

Stefan-Boltzmann law states that the total radiant power emitted per unit area of a black body is directly proportional to which power of absolute temperature $T$?

Accepted Answer

D) $T^4$

Answer

A) $T^1$

Answer

B) $T^2$

Answer

C) $T^3$

Question 13

How much heat energy is required to raise the temperature of a 2 kg aluminum block ($c = 900 ext{ J/(kg}\cdot ext{K)}$) from $20^\circ ext{C}$ to $50^\circ ext{C}$?

Accepted Answer

A) 54,000 J

Answer

B) 27,000 J

Answer

C) 18,000 J

Answer

D) 108,000 J

Question 14

Which mode of heat transfer involves the actual physical movement of fluid mass carrying heat energy?

Accepted Answer

B) Convection

Answer

A) Conduction

Answer

C) Radiation

Answer

D) Induction

Question 15

A bimetallic strip consists of two different metallic strips joined together. It bends when heated because the metals have different:

Accepted Answer

C) Coefficients of linear expansion

Answer

A) Thermal conductivities

Answer

B) Specific heat capacities

Answer

D) Latent heats of fusion

Question 16

What is the correct SI unit of specific latent heat ($L$)?

Accepted Answer

A) $	ext{J}\cdotkg^{-1}$

Answer

B) $	ext{J}\cdotkg^{-1}\cdot	ext{K}^{-1}$

Answer

C) $	ext{W}\cdotkg^{-1}$

Answer

D) $	ext{J}\cdot	ext{K}^{-1}$

Question 17

Calculate the heat energy required to completely melt 0.5 kg of ice at $0^\circ ext{C}$ given $L_f = 3.33 imes 10^5 ext{ J/kg}$.

Accepted Answer

A) $1.665 	imes 10^5	ext{ J}$

Answer

B) $3.330 	imes 10^5	ext{ J}$

Answer

C) $6.660 	imes 10^5	ext{ J}$

Answer

D) $0.8325 	imes 10^5	ext{ J}$

Question 18

According to Newton's Law of Cooling, the rate of loss of heat from a hot body is directly proportional to:

Accepted Answer

B) Temperature difference between the body and surroundings

Answer

A) Absolute temperature of the body

Answer

C) Square of temperature difference

Answer

D) Cube of body temperature

Question 19

What is the absorptive power ($a$) of an ideal black body for thermal radiation of all wavelengths?

Accepted Answer

C) 1

Answer

A) 0

Answer

B) 0.5

Answer

D) Infinite

Question 20

Which physical effect forms the working principle of a thermocouple temperature measurement sensor?

Accepted Answer

B) Seebeck effect

Answer

A) Peltier effect

Answer

C) Thomson effect

Answer

D) Joule effect

Grade 11 : Physics - Thermal Properties (Set 6)