Question

У туристів останнього дня походу лишилося в примусі 100 мл бензину. Чи зможуть вони закип*ятити трилітровий казанок води якщо ккд примуса дорівнює 30 %? Уважайте, що початкова температура води дорівнює 20 градусів, а густина бензину дорівнює 700 кг\м кубічний

Answer 1

Q=c*m*Δt=1*3*(100-20)=1*3*80=240(ккал)  
необходимое к-во тепла для нагревания 3 литров воды до кипения;
g=10200ккал/кг  теплотворная способность бензина;
100мл=0,1л=0,001м³;
0,7*10200*0,3=2142ккал;
 Ответ: Для нагрева воды до кипения достаточно оставшегося
             бензина.

Answer 2

Can tourists boil a three-liter pot of water if they have 100 ml of gasoline left and the stove's fuel efficiency is 30%?

To determine if the tourists can boil a three-liter pot of water with 100 ml of gasoline and a stove fuel efficiency of 30%, we need to calculate the energy content of the gasoline and compare it to the energy required to boil the water.

First, let's calculate the energy content of the gasoline. The energy content of gasoline is typically measured in megajoules per liter (MJ/L). To convert the given density of gasoline (700 kg/m^3) to liters, we can use the formula:

Volume (L) = Mass (kg) / Density (kg/m^3)

Using the given density of gasoline (700 kg/m^3) and the volume of gasoline (100 ml), we can calculate the mass of gasoline:

Mass (kg) = Volume (L) * Density (kg/m^3)

Next, we can calculate the energy content of the gasoline using the formula:

Energy (MJ) = Volume (L) * Energy Content (MJ/L)

To find the energy content of gasoline, we need to search for its energy content in megajoules per liter.

According to the search results, the energy content of gasoline is approximately 34.2 megajoules per liter [[1]]. Using this value, we can calculate the energy content of the 100 ml of gasoline.

Now, let's calculate the energy required to boil the three-liter pot of water. The specific heat capacity of water is approximately 4.18 joules per gram per degree Celsius. To convert the three liters of water to grams, we can use the formula:

Mass (g) = Volume (L) * Density (g/L)

Using the density of water (1000 g/L) and the volume of water (3 L), we can calculate the mass of water.

Next, we can calculate the energy required to raise the temperature of the water from 20 degrees Celsius to its boiling point (100 degrees Celsius) using the formula:

Energy (J) = Mass (g) * Specific Heat Capacity (J/g°C) * Temperature Difference (°C)

Finally, we can convert the energy required to boil the water from joules to megajoules:

Energy (MJ) = Energy (J) / 1,000,000

By comparing the energy content of the gasoline to the energy required to boil the water, we can determine if the tourists will be able to boil the three-liter pot of water.

Please wait a moment while I perform the calculations.