Question

Когда шар массой 2 кг получила количество теплоты 6,9 кДж, ее температура увеличилась от 30 до 45 градусов Цельсия. Определите удельную теплоемкость материала шара. С чего она может быть изготовлена?

Answer 1

Дано: 

m = 2кг
Q = 6,9кДж = 6900Дж
t₁ = 30°C
t₂ = 45°C

Рабочие формулы: 

Q = mc(t₂ – t₁)
c = $\frac{Q}{m(t_2-t_1)}$

Решение (запишу без наименований, через редактор латекс): 

$\frac{6900}{2(45-30)}=\frac{6900}{30}=230$

Ответ₁: удельная теплоёмкость (c) равна 230 Джоулей, делённых на килограмм, умноженный на градус Цельсия. 
Ответ₂: материал, из которого сделан шар – это олово (по таблице удельной теплоёмкости веществ).

Answer 2

Calculation of Specific Heat Capacity and Material Composition

To determine the specific heat capacity of the material of the sphere, we can use the formula:

Q = mcΔT

Where: - Q is the amount of heat transferred to the sphere (6.9 kJ) - m is the mass of the sphere (2 kg) - c is the specific heat capacity of the material - ΔT is the change in temperature (45°C - 30°C = 15°C)

Rearranging the formula, we can solve for c:

c = Q / (m * ΔT)

Substituting the given values:

c = 6.9 kJ / (2 kg * 15°C)

Now, let's calculate the specific heat capacity.

Calculation:

c = 6.9 kJ / (2 kg * 15°C)

Converting kJ to J:

c = 6.9 kJ * 1000 J/kJ / (2 kg * 15°C)

c = 6900 J / (2 kg * 15°C)

c = 230 J / (kg * °C)

Therefore, the specific heat capacity of the material of the sphere is 230 J / (kg * °C).

Now, let's discuss the possible materials that the sphere could be made of.

Possible Materials for the Sphere:

The specific heat capacity of a material can vary depending on its composition. Here are a few possible materials that the sphere could be made of:

1. Water has a specific heat capacity of approximately 4186 J / (kg * °C) However, since the calculated specific heat capacity of the sphere is 230 J / (kg * °C), it is unlikely that the sphere is made of water.

2. Aluminum has a specific heat capacity of approximately 900 J / (kg * °C) Since the calculated specific heat capacity of the sphere is lower than that of aluminum, it is also unlikely that the sphere is made of aluminum.

3. Iron has a specific heat capacity of approximately 450 J / (kg * °C) Again, since the calculated specific heat capacity of the sphere is lower than that of iron, it is unlikely that the sphere is made of iron.

4. Glass has a specific heat capacity of approximately 840 J / (kg * °C) While the calculated specific heat capacity is lower than that of glass, it is closer compared to the previous materials mentioned. Therefore, it is possible that the sphere is made of glass.

5. Plastic materials can have a wide range of specific heat capacities depending on their composition. Without specific information about the type of plastic, it is difficult to determine if the sphere is made of plastic.

It is important to note that the specific heat capacity alone is not sufficient to determine the exact material of the sphere. Other properties, such as density, conductivity, and appearance, would need to be considered for a more accurate identification.

In conclusion, based on the given information, it is possible that the sphere is made of glass due to its relatively closer specific heat capacity compared to other materials mentioned. However, without further information, it is difficult to determine the exact material composition of the sphere.