Thermal properties of matter practice · Medium

Four pieces of iron heated in a furnace to different temperatures show different colours listed below. Which one has the highest temperature

A piece of platinum can be sealed successfully into soda glass but not a piece of copper because

Statement A: Heat transfer by conduction and convection require a material medium.
Statement B: Heat transfer by radiation doesn't effect the medium through which it passes.

By what percentage should the pressure of a given mass of a gas be increased so as to decrease its volume by $20 \%$ at constant temperature?

Two thermometers are constructed in the same way except that one has a spherical bulb and the other a cylindrical bulb; which one will respond quickly to temperature changes

The coefficient of linear expansion of brass and steel are ${\alpha _1}$ and ${\alpha _2}$. If we take a brass rod of length ${l_1}$ and steel rod of length ${l_2}$ at ${0^0}C$, their difference in length $\left( {{l_2} - {l_1}} \right)$ will remain the same at a temperature if

The latent heat of vaporisation of a substance is always

Rate of transfer of heat is maximum in the case of

Statement-I: Two rods of the same material have the same lengths but diameter are in the ratio of $1:2.$ If $1000 \mathrm{cal}$ of heat is supplied to the two rods separately the ratio of their linear expansion is $4:1.$
Statement-II: The linear expansion $e=l \alpha \Delta t$

Among the following rods made of same material, the one that can conduct more heat in a given time when their ends are maintained at the same temperature differences

Statement-I: The linear coefficients of expansion of a crystal along three perpendicular axes are $\alpha, \frac{-\alpha}{2}, \frac{\alpha}{5}.$ Its volume coefficient is $\frac{7 \alpha}{10}$
Statement-II: For anisotropic solids $\gamma=\alpha_x+\alpha_y+\alpha_z$.

Assertion (A): Steel rods are used in R.C.C
Reason (R): Both steel and R.C.C have almost same values of coefficient of linear expansion.

The density of mercury is $13.6 \mathrm{~g} \mathrm{~cm}^{-3}$ at $0^{\circ} \mathrm{C}$ and its coefficient of cubical expansion is $1.82 \times 10^{-4}{ }^{\circ} \mathrm{C}^{-1}$. Calculate the density of mercury at $50^{\circ} \mathrm{C}$.

Assertion (A): Pressure of gas is same everywhere inside a closed container
Reason (R): The gas molecules undergo elastic collisions among themselves and also with the walls

What force should be applied to the ends of steel rod of a cross sectional area 10 cm2 to revent it from elongation when heated from 273K to 303K. $\left( {\alpha = 1 \times {{10}^{ - 5}}/{\,^{\,0}}C,y = 2 \times {{10}^{11}}\,w/{m^2}} \right)$

Certain amount of heat is given to $100 \mathrm{~g}$ of copper to increase its temperature by $21^{\circ} \mathrm{C}$. If the same amount of heat is given to $50 \mathrm{~g}$ of water, then the rise in its temperature is

(Take, specific heat capacity of copper

$=400 \mathrm{Jkg}^{-1} \mathrm{~K}^{-1}$ and that for water

$=4200 \mathrm{~J} \mathrm{~kg}^{-1} \mathrm{~K}^{-1}$ )

Assertion: A change in the temperature of a body causes change in its dimensions.
Reason: The dimensions of a body decrease due to the increase in its temperature.

Two beakers A and B are filled to the brim with water at ${4^0}C$ . When A is heated and B is cooled, the water

When a copper ball is heated, the largest percentage increase will occur in its

Assertion: Maximum air flow due to convection does not occur at the north pole but it occurs at $30^{\circ} \mathrm{N}$.
Reason: There is maximum temperature difference between equator and $30^{\circ} \mathrm{N}$.

A black body at a temperature of 1640 K has the wavelength corresponding to maximum emission equal to $1.75\mu$. Assuming the moon to be a perfectly black body, the temperature of the moon, if the wavelength corresponding to maximum emission is $14.35\mu$ is

A body having a temperature of $27^{\circ} \mathrm{C}$ is kept in a room having a temperature of $27^{\circ} \mathrm{C}$. Does the body emit any radiation in this case when the room temperature is the same as body temperature?

A thermometer graduated according to a linear scale reads a value ${x_0}$, when in contact with boiling water and ${x_0}\mathrm{/}3$ when in contact with ice. What is the temperature of an object in $^\circ C$, if this thermometer in the contact with the object reads ${x_0}\mathrm{/}2?$

For a cube, cylinder and sphere, linear dimension is same and these are made up by same material and having same surface and same temperature it these are placed in same temperature surrounding then find out the order of rate of heat loss and rate of cooling.

A liter of air is heated from ${27^0}C$ to ${177^0}C$ at constant pressure. Find its volume

Inside a cylinder closed at both ends is a movable piston. On one side of the piston is a mass $m$ of a gas, and on the other side a mass 2 $m$ of the same gas. What fraction of the volume of the cylinder will be occupied by the larger mass of the gas when the piston is in equilibrium? The temperature is the same throughout.

Which of the following statement does not hold good for thermal radiation?

The sprinkling of water reduces slightly the temperature of a closed room because

We find that the temperature of air decreases as one goes up from the earth’s surface because

An iron ball having a surface area of $200 \mathrm{~cm}^2$ and at a temperature of $527^{\circ} \mathrm{C}$ is placed in an enclosure at $27^{\circ} \mathrm{C}$. If the surface emissivity of iron be $0.4,$ at what rate is heat being lost by radiation by the ball?