Thermal properties of matter practice · Medium

Assertion: The temperature at which Centigrade and Fahrenheit thermometers read the same is $-40^{\circ}$.
Reason: There is no relation between Fahrenheit and Centigrade temperature.

Heat travels through vacuum by

Of the following thermometers, the one which can be used for measuring a rapidly changing temperature is a

According to Wein's displacement law

The lengths and radii of two rods made of same material are in the ratios 1:2 and 2:3 respectively. If the temperature difference between the ends for the two rods be the same, then in the steady state, the amount of heat flowing per second through them will be in the ratio

Assertion: The coefficient of volume expansion has dimension $\mathrm{K}^{-1}$.
Reason: The coefficient of volume expansion is defined as the change in volume per unit volume per unit change in temperature.

Due to the change in mains voltage, the temperature of an electric bulb rises from $3000 \mathrm{~K}$ to $4000 \mathrm{~K}$. What is the percentage rise in electric power consumed?

The equation for an ideal gas is $PV = RT,$ where $V$ represents the volume of

The surface temperature of the sun is

How many reference temperature/s is/are used to make the Kelvin temperature scale?

In Boyle’s law what remains constant

Statement-I: A thin rod and a thick rod made of same material having same length are given same amount of heat $\theta$. Then the thin rod expands more.
Statement-II: The linear expansion depends upon initial length of the rod only.

The length of a steel rod exceeds that of a brass rod by $5 \mathrm{~cm}$. If the difference in their lengths remains same at all temperatures, then the length of brass rod will be: respectively)

If the radius of a star is R and it acts as a black body, what would be the temperature of the star, in which the rate of energy production is Q (σ stands for stefan’s constant)

Density of substance at ${0^0}C$ is 10 g/cc and at ${100^0}C$, its density is 9.7 g/cc. The coefficient of linear expansion of the substance is

Statement I: The reflection coefficient of a black
body is zero.

Statement II: Black body absorbs all the
radiation incident on it.

The cause of Fraunhoffer lines is

In anomalous expansion of water, at what temperature, the density of water is maximum?

Statement 1: Latent heat of fusion of ice is $336000 \mathrm{~Jkg}^{-1}$
Statement 2: Latent heat refers to change of state without any change in temperature.

A blue glass when heated will glow with

Substance having very small coefficient of linear expansion, among the following is

A spherical body of emissivity $e=0.7$ and surface area $A$ is Placed inside a perfect black body maintained at temperature $T$, then energy radiated per second by black body will be

The saturation vapour pressure of water at ${100^0}C$ is

At temperature $'T'$, the power radiated by a body is $Q$ watt. At the temperature $3T$ the power radiated by it will be

During process of melting, thermal energy that is absorbed during process of melting is called:

A black body is at $727^{\circ} \mathrm{C}$. It emits energy at a rate which is proportional to

Assertion: $H_2$ is found more as compared to $N_2$ in earth's upper atmosphere.
Reason: $N_2$ is heavier than $H_2.$

Temperatures of two stars are in the ratio 3:2. If wavelength of maximum intensity of first body is 4000 $A$, what is corresponding wavelength second body?

On a cold morning, a metal surface will feel colder to touch than a wooden surface because

Two thermally insulated vessels 1 and 2 are filled with air at temperatures $\left( {{T_1},{T_2}} \right)$ volume $\left( {{V_1},{V_2}} \right)$ and pressure $\left( {{P_1},{P_2}} \right)$ respectively. If the valve joining the two vessels is opened, the temperature inside the vessel at equilibrium will be