Question

В сосуд с водой при температуре 0 градусов опустили цилиндрический медный стержень, нагретый до температуры 300 градусов. после чего температура воды повысилась до 23 градусов. Объем воды 10 литров, площадь сечения стержня 20 куб. см. Определить длину стержня. Нагреванием сосуда, а также потерями тепла пренебречь

Answer 1

Делаем уравнение теплового баланса (вода-медь). Из него находим массу меди. Зная плотность меди находим V медного стержня. V делим на S сечения получаем длину стержнЯ

Answer 2

Problem Analysis

We are given a cylindrical copper rod that is initially heated to a temperature of 300 degrees Celsius. The rod is then submerged in a vessel containing 10 liters of water at a temperature of 0 degrees Celsius. After the rod is submerged, the temperature of the water rises to 23 degrees Celsius. We need to determine the length of the copper rod. We are also told to neglect the heating of the vessel and any heat losses.

Solution

To solve this problem, we can use the principle of heat transfer. The heat gained by the water is equal to the heat lost by the copper rod. We can use the formula:

Q = mcΔT

Where: - Q is the heat gained or lost - m is the mass of the substance - c is the specific heat capacity of the substance - ΔT is the change in temperature

In this case, the heat gained by the water is equal to the heat lost by the copper rod. We can express this as:

m_water * c_water * ΔT_water = m_rod * c_rod * ΔT_rod

Since the volume of water and the specific heat capacity of water are given, we can calculate the mass of water using the formula:

m_water = V_water * ρ_water

Where: - V_water is the volume of water - ρ_water is the density of water

We can assume the density of water is 1 kg/L.

Now, let's calculate the mass of water:

m_water = 10 L * 1 kg/L = 10 kg

The specific heat capacity of water is approximately 4.18 J/g°C.

Now, let's calculate the change in temperature of the water:

ΔT_water = 23°C - 0°C = 23°C

Now, let's calculate the heat gained by the water:

Q_water = m_water * c_water * ΔT_water

Substituting the values:

Q_water = 10 kg * 4.18 J/g°C * 23°C

To calculate the heat lost by the copper rod, we need to know the mass and specific heat capacity of copper. Unfortunately, this information is not provided in the question. Therefore, we cannot proceed with the calculation.

In order to determine the length of the copper rod, we need additional information.