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Question: Suppose the temperature of a gas iswhen it is at the boiling point of water. What then is the limiting value of the ratio of the pressure of the gas at that boiling point to its pressure at the triple point of water? (Assume the volume of the gas is the same at both temperatures).

The initial length L, change in temperature $\mathbf{鈻�}\mathbf{T}$, and change in length $\mathbf{鈻�}\mathbf{L}$of four rods are given in the following table. Rank the rods according to their coefficients of thermal expansion, greatest first.

In a certain experiment, a small radioactive source must move at selected, extremely slow speeds. This motion is accomplished by fastening the source to one end of an aluminum rod and heating the central section of the rod in a controlled way. If the effective heated section of the rod in Figure has length $\mathbf{d}\mathbf{=}\mathbf{2}\mathbf{.00}\mathbf{\text{鈥塩尘}}$, at what constant rate must the temperature of the rod be changed if the source is to move at a constant speed of $\mathbf{100}\mathbf{\text{鈥塶尘/蝉}}$?

As a result of a temperature rise of $\mathbf{32}{\mathbf{}}^{\mathbf{0}}\mathbf{C}$, a bar with a crack at its center buckles upward (Figure). If the fixed distance ${\mathbf{L}}_{\mathbf{0}}\mathbf{\text{鈥夆赌�}}\mathbf{}\mathbf{is}\mathbf{}\mathbf{\text{鈥夆赌�}}\mathbf{3}\mathbf{.77}\mathbf{}\mathbf{m}\mathbf{}$ and the coefficient of linear expansion of the bar is $\mathbf{25}\mathbf{脳}\mathbf{}{\mathbf{10}}^{\mathbf{鈭�}\mathbf{6}}{\mathbf{/}}^{\mathbf{0}}\mathbf{C}$, find the rise x of the center.

One way to keep the contents of a garage from becoming too cold on a night when a severe subfreezing temperature is forecast is to put a tub of water in the garage. If the mass of the water is $\mathbf{125}\mathbf{\text{鈥�}}\mathbf{}\mathbf{kg}\mathbf{}$and its initial temperature is$\mathbf{20}\mathbf{掳}\mathbf{C}\mathbf{}$, (a) how much energy must the water transfer to its surroundings in order to freeze completely and (b) what is the lowest possible temperature of the water and its surroundings until that happens?

A small electric immersion heater is used to heat $\mathbf{\text{100g}}$of water for a cup of instant coffee. The heater is labeled 鈥�$\mathbf{200}\mathbf{}\mathbf{watts}$鈥� (it converts electrical energy to thermal energy at this rate). Calculate the time required to bring all this water from$\mathbf{23.0}\mathbf{掳}\mathbf{C}\mathbf{}\mathbf{to}\mathbf{}\mathbf{100}\mathbf{掳}\mathbf{C}$, ignoring any heat losses.

A certain substance has a mass per mole of 50.0 g/mol. When 314 J is added as heat to a 30.0 g sample, the sample鈥檚 temperature rises from 25.0掳颁 to 45.0掳颁. (a) What is the specific heat and (b) What is the molar specific heat of this substance? (c) How many moles are in the sample?

Calculate the minimum amount of energy, in joules, required to completely melt$\mathbf{\text{130g}}$of silver initially at$\mathbf{\text{15.0掳颁}}$.

In a solar water heater, energy from the Sun is gathered by water that circulates through tubes in a rooftop collector. The solar radiation enters the collector through a transparent cover and warms the water in the tubes; this water is pumped into a holding tank. Assume that the efficiency of the overall system is$\mathbf{20}\mathit{\%}$ (that is, $\mathbf{80}\mathit{\%}$of the incident solar energy is lost from the system).What collector area is necessary to raise the temperature of$\mathbf{200}\mathbf{}\mathbf{\text{L}}$ of water in the tank from $\mathbf{\text{20掳颁}}$to$\mathbf{40}\mathbf{\text{掳颁}}$ in$\mathbf{1}\mathbf{.0}\mathbf{}\mathbf{\text{鈥塰}}$ when the intensity of incident sunlight is $\mathbf{700}\mathbf{}{\mathbf{\text{W/m}}}^{\mathbf{\text{2}}}$?

Two constant-volume gas thermometers are assembled, one with nitrogen and the other with hydrogen. Both contain enough gas so that.(a) What is the difference between the pressures in the two thermometers if both bulbs are in boiling water? (Hint: See Fig. 18-6) (b) Which gas is at higher pressure?