Question

Six objects are placed in a 500℉ (260℃) oven and allowed to reach thermal equilibrium. Each object has a mass of 1.0 kg. The specific heat and thermal conductivity of each substance are denoted by c and k.

 

Part B:

When removing the objects from the oven, you accidentally touch each one with your hand. Rank these objects on the basis of how hot they feel.

Rank from largest to smallest. To rank items as equivalent, overlap them.

 

Part C:

Each of the objects is immediately dunked in an identical tub of cold water. The tubs are quickly sealed and insulated. Rank the objects on the basis of theirtemperature on reaching equilibrium with the water.

Rank from largest to smallest. To rank itens as equivalent, overlap them.

 

Answer 1

The main concepts used to solve this problem are specific heat and Thermal conductivity.

Initially, Use the definition of the specific heat. Later, use the expression of the thermal conductivity to identify the rankings. Finally, Use the fact that the object and its surroundings are at the same temperature at equilibrium.

Thermal conductivity is the property of a material to conduct heat. It is defined as the heat energy transferred per unit time and surface area. The objects with low thermal conductivity have a low rate of heat transfer across materials than those with high thermal conductivity.

Specific heat is defined as the amount of heat per unit mass required to raise the temperature of a substance by one degree Celsius. The high specific heat implies that it takes a lot of energy to raise its temperature. The water has high specific heat.

Rank these objects based on their temperatures when removed from the oven.

The specific heat of a substance is the amount of heat energy needed to raise the temperature of 1.0 kg of the essence by $1℃$.

The specific heat of the substance depends on the material of the essence. Its value of different for different meanings.

Use the concept of thermal equilibrium to identify the rankings based on their temperature.

Thermal equilibrium is when there is no heat flow between two physical systems.

At thermal equilibrium, an object and its surroundings are at the same temperature.

So, all the substances in an oven maintain the same temperature. Because at thermal equilibrium, the implications don't depend on their specific heat and thermal conductivity.

Ranking from largest to smallest is as follows:

$\begin{array}{c}\mathrm{I}\mathrm{r}\mathrm{o}\mathrm{n}\mathrm{s}\mathrm{k}\mathrm{i}\mathrm{l}\mathrm{l}\mathrm{e}\mathrm{t}=\mathrm{w}\mathrm{e}\mathrm{l}\mathrm{l}\mathrm{d}\mathrm{o}\mathrm{n}\mathrm{e}\mathrm{s}\mathrm{t}\mathrm{e}\mathrm{a}\mathrm{k}=\mathrm{g}\mathrm{l}\mathrm{a}\mathrm{s}\mathrm{s}\mathrm{c}\mathrm{a}\mathrm{s}\mathrm{s}\mathrm{e}\mathrm{r}\mathrm{o}\mathrm{l}\mathrm{e}\mathrm{d}\mathrm{i}\mathrm{s}\mathrm{h}=\mathrm{a}\mathrm{l}\mathrm{u}\mathrm{m}\mathrm{i}\mathrm{n}\mathrm{u}\mathrm{m}\mathrm{p}\mathrm{o}\mathrm{t}\\ =\mathrm{w}\mathrm{o}\mathrm{o}\mathrm{d}\mathrm{e}\mathrm{n}\mathrm{c}\mathrm{u}\mathrm{t}\mathrm{t}\mathrm{i}\mathrm{n}\mathrm{g}\mathrm{b}\mathrm{o}\mathrm{a}\mathrm{r}\mathrm{d}=\mathrm{s}\mathrm{i}\mathrm{l}\mathrm{v}\mathrm{e}\mathrm{r}\mathrm{i}\mathrm{n}\mathrm{g}\mathrm{o}\mathrm{t}\end{array}$

The rankings are found using the fact that at equilibrium the temperature of the all substances are same.

 

Ranking from largest to smallest is as follows:

$\begin{array}{c}\mathrm{I}\mathrm{r}\mathrm{o}\mathrm{n}\mathrm{s}\mathrm{k}\mathrm{i}\mathrm{l}\mathrm{l}\mathrm{e}\mathrm{t}=\mathrm{w}\mathrm{e}\mathrm{l}\mathrm{l}\mathrm{d}\mathrm{o}\mathrm{n}\mathrm{e}\mathrm{s}\mathrm{t}\mathrm{e}\mathrm{a}\mathrm{k}=\mathrm{g}\mathrm{l}\mathrm{a}\mathrm{s}\mathrm{s}\mathrm{c}\mathrm{a}\mathrm{s}\mathrm{s}\mathrm{e}\mathrm{r}\mathrm{o}\mathrm{l}\mathrm{e}\mathrm{d}\mathrm{i}\mathrm{s}\mathrm{h}=\mathrm{a}\mathrm{l}\mathrm{u}\mathrm{m}\mathrm{i}\mathrm{n}\mathrm{u}\mathrm{m}\mathrm{p}\mathrm{o}\mathrm{t}\\ =\mathrm{w}\mathrm{o}\mathrm{o}\mathrm{d}\mathrm{e}\mathrm{n}\mathrm{c}\mathrm{u}\mathrm{t}\mathrm{t}\mathrm{i}\mathrm{n}\mathrm{g}\mathrm{b}\mathrm{o}\mathrm{a}\mathrm{r}\mathrm{d}=\mathrm{s}\mathrm{i}\mathrm{l}\mathrm{v}\mathrm{e}\mathrm{r}\mathrm{i}\mathrm{n}\mathrm{g}\mathrm{o}\mathrm{t}\end{array}$