Thermal properties of matter practice · Mixed difficulty

A liquid cools down from ${70^0}C$ to ${60^0}C$ in 5 minutes . The time taken to cool it from ${60^0}C$ to ${50^0}C$ will be

Robin wants to shove rubber pipe up a plastic tap. The problem is that the pipe's diameter is smaller than that required to secure a tight fit. So Robin switches on a halfdryer on and pointed it towards the pipe. He found that now the pipe fitted in easily. Why is this so?

A cup of tea cools from $70^{\circ} {C}$ to $60^{\circ} {C}$ in 5 minutes and to $50^{\circ} {C}$ in next 7 minutes. Assuming Newton's law of cooling, the temperature of surroundings is

In determining the temperature of a distant star, one makes use of

Assertion: Fahrenheit is the smallest unit measuring temperature.
Reason: Fahrenheit was the first temperature scale used for measuring temperature.

The resistance of a resistance thermometer has values $2.71$ and $3.70\,\,ohm$ at ${10^0}C$ and ${100^0}C$. The temperature at which the resistance is $3.26\,\,ohm$ is

Wien's law is concerned with

A liquid having coefficient of cubical expansion $\gamma$ is filled in the container having coefficient of linear expansion $\alpha$. If on heating the liquid overflows, then which of the following relations is correct?

A uniform metal rod (bar pendulum), which is coefficient of linear expansion is $2 \times 10^{-6} /{ }^{\circ} \mathrm{C}$, the period of the pendulum will have percentage increase, if room temperature rise by $10^{\circ} \mathrm{C}$.

The Coefficient of apparent expansion of a liquid when determined using two different vessels $A\;\mathrm{and}\;B\;\mathrm{are}\;{\lambda _1}$ and ${\lambda _2},$ respectively. If the coefficient of linear expansion of the vessel $A\;\mathrm{is}\;\alpha ,$ the coefficient of linear expansion of vassel $B$ is

The freezing point on a thermometer is marked as ${20^0}C$ and the boiling point as ${150^0}C$. A temperature of ${60^0}C$ on this thermometer will be read as

A simple seconds pendulum is constructed out of a very thin string of thermal coefficient of linear expansion $\alpha=20 \times 10^{-4} /{ }^{\circ} \mathrm{C}$ and a heavy particle attached to one end. The free end of the string is suspended from the ceiling of an elevator at rest. The pendulum keeps correct time at $0^{\circ} \mathrm{C}$. When the temperature rises to $50^{\circ} \mathrm{C}$, the elevator operator of mass $60 \mathrm{~kg}$ being a student of Physics accelerates the elevator vertically, to have the pendulum correct time. Find the apparent weight of the operator when the pendulum keeps correct time at $50^{\circ} \mathrm{C}$. (Take $g=10 \mathrm{~m} / \mathrm{s}^2$ )

The spectrum from a black body radiation is a