Question

Температура нагревателя 150 С, А ХОЛОДИЛЬНИКА 20 С,.от нагревателя взято 10^5 кДж теплоты. как велика работа. произведенная машиной,если машина идеальная?

Answer 1

10:5 кДж-это сколько Джоулей? Находим КПД машинытемпература в кельвинахКПД= Тн-Тх  /Тн=  (150+273)-(-20+273)/(150+273)=0,40= 40%работа произведенная машинойА=10.5 кДж *0,40=4,2кДж

Answer 2

Calculation of Work Done by an Ideal Machine

To calculate the work done by an ideal machine, we need to use the formula:

Work = Heat absorbed - Heat rejected

Given the following information: - Temperature of the heater (T1) = 150°C - Temperature of the refrigerator (T2) = 20°C - Heat absorbed (Q1) = 10^5 kJ

We can calculate the heat rejected (Q2) using the formula:

Q2 = Q1 - Work

Now let's substitute the given values into the formula:

Q2 = 10^5 kJ - Work

To calculate the work done, we need to convert the temperatures from Celsius to Kelvin, as the temperature scale used in thermodynamics is Kelvin.

Converting the temperatures: - T1 = 150°C + 273.15 = 423.15 K - T2 = 20°C + 273.15 = 293.15 K

Now we can calculate the work done by the machine.

Work = Q1 - Q2

Substituting the values:

Work = 10^5 kJ - Q2

To find Q2, we can use the formula for heat transfer:

Q2 = m * c * ΔT

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

Since we don't have information about the mass or specific heat capacity of the substance, we cannot calculate the exact value of Q2 or the work done by the machine.

However, if we assume that the mass and specific heat capacity are constant, we can calculate an approximate value for the work done using the given temperatures.

Please note that this calculation is based on assumptions and may not reflect the exact value.

Let's assume: - Mass (m) = 1 kg - Specific heat capacity (c) = 4.18 kJ/(kg·K) (approximate value for water)

Using these assumptions, we can calculate the approximate value of Q2:

Q2 = m * c * ΔT

Q2 = 1 kg * 4.18 kJ/(kg·K) * (423.15 K - 293.15 K)

Q2 ≈ 1 kg * 4.18 kJ/(kg·K) * 130 K

Q2 ≈ 543.4 kJ

Now we can calculate the approximate value of the work done:

Work = 10^5 kJ - Q2

Work ≈ 10^5 kJ - 543.4 kJ

Work ≈ 99456.6 kJ

Therefore, the approximate value of the work done by the ideal machine is approximately 99456.6 kJ.

Please note that this calculation is based on assumptions and may not reflect the exact value. The actual work done by the machine depends on various factors such as the specific heat capacity and mass of the substance being heated or cooled.