Question

4. Баба-Яга решила истопить баньку для Иванушки Дурака. В Бане у Бабы-Яги имеется медный котёл массой 50 кг, вмещающий 100 литров воды и некоторый запас дров. Какое количество дров должна сжечь Баба-Яга в топке, чтобы нагреть Воду до температуры 95°C, если дрова в топке сгорают полностью, а на нагрев котла с водой уходит 80% выделяемой при сгорании дров количества теплоты (остальная энергия вылетает в трубу и греет окружающую среду).

Answer 1

Ответ:

m=cmt+CMt/q*0.8=4200*100*95+380*50*95/1.26*10^7*0.8=3.5 кг

Объяснение:

Answer 2

Calculation of the Amount of Wood Needed to Heat the Water in Baba Yaga's Bathhouse

To calculate the amount of wood Baba Yaga needs to burn in order to heat the water in her bathhouse, we need to consider the mass of the copper cauldron, the volume of water it can hold, and the temperature increase required.

Given information: - Mass of the copper cauldron: 50 kg - Volume of water the cauldron can hold: 100 liters - Desired temperature increase: from an initial temperature to 95°C - Wood burns completely in the stove - 80% of the heat generated by burning the wood is transferred to the water in the cauldron, while the remaining energy is lost to the surroundings

To calculate the amount of wood needed, we can follow these steps:

1. Calculate the heat capacity of the water in the cauldron. 2. Calculate the heat energy required to raise the temperature of the water. 3. Calculate the heat energy released by burning the wood. 4. Determine the amount of wood needed.

Let's calculate each step in detail.

Step 1: Calculate the Heat Capacity of the Water

The heat capacity of water is approximately 4.18 J/g°C. Since we know the volume of water in liters and the density of water is approximately 1 g/mL, we can calculate the mass of the water using the formula:

Mass of water (in grams) = Volume of water (in liters) x Density of water (in g/mL)

Converting the volume of water from liters to milliliters:

Volume of water (in milliliters) = Volume of water (in liters) x 1000

Now we can calculate the mass of the water:

Mass of water (in grams) = Volume of water (in milliliters) x Density of water (in g/mL)

Step 2: Calculate the Heat Energy Required to Raise the Temperature of the Water

The formula to calculate the heat energy required to raise the temperature of a substance is:

Heat energy (in Joules) = Mass of the substance (in grams) x Specific heat capacity of the substance (in J/g°C) x Temperature increase (in °C)

In this case, the substance is water, and we already have the mass of the water and the specific heat capacity of water. The temperature increase is from the initial temperature to 95°C.

Step 3: Calculate the Heat Energy Released by Burning the Wood

Since the wood burns completely, all the energy released by burning the wood is transferred to the water in the cauldron. However, only 80% of this energy is used to heat the water, while the remaining 20% is lost to the surroundings.

Step 4: Determine the Amount of Wood Needed

To determine the amount of wood needed, we need to compare the heat energy required to raise the temperature of the water with the heat energy released by burning the wood.

If the heat energy released by burning the wood is greater than or equal to the heat energy required to raise the temperature of the water, then Baba Yaga has enough wood to heat the water. Otherwise, she needs to burn more wood.

Let's perform the calculations.

Calculation:

Step 1: Calculate the Heat Capacity of the Water

- Volume of water: 100 liters - Density of water: 1 g/mL

Converting the volume of water from liters to milliliters:

Volume of water (in milliliters) = 100 liters x 1000 = 100,000 milliliters

Calculating the mass of the water:

Mass of water (in grams) = 100,000 milliliters x 1 g/mL = 100,000 grams

Step 2: Calculate the Heat Energy Required to Raise the Temperature of the Water

- Mass of water: 100,000 grams - Specific heat capacity of water: 4.18 J/g°C - Temperature increase: from initial temperature to 95°C

Heat energy required = 100,000 grams x 4.18 J/g°C x (95°C - initial temperature)

Please provide the initial temperature in order to complete the calculation.