Question

Известно что в 1 куб метре воздуха(при отсутствии в помещении людей) содержится примерно 2600 бактерий. После 2-ух уроков в непроветриваемом классе количество бактерий в 1 куб м увеличивается до 13500. Проветривание помещения в течение 10 минут снимает количество бактерий в 3 раза. Узнайте : 1) Сколько бактерий в классе до занятий? 2) Сколько бактерий в классе после 4-ёх уроков, если класс не проветртвается? 3) Сколько бактерий в классе после 7-ми уроков, если класс не проветривается? 4) Сколько бактерий в классе будет после 4-ёз и 7-ми уроков, если перед изменением помещение проверить? Дополнительные данные : высота кабинета - 3,5 м, длина - 13 м, широта 5,5м​

Answer 1

Ответ:

тоол

Объяснение:

Answer 2

According to the information provided, the number of bacteria in 1 cubic meter of air (in the absence of people in the room) is approximately 2600. After 2 lessons in an unventilated classroom, the number of bacteria in 1 cubic meter increases to 13500. Ventilating the room for 10 minutes reduces the number of bacteria by 3 times.

To answer the questions, we need to calculate the number of bacteria in the classroom before and after the lessons, considering the given dimensions of the room.

1) Сколько бактерий в классе до занятий?

To calculate the number of bacteria in the classroom before the lessons, we need to find the volume of the classroom and multiply it by the initial concentration of bacteria.

Given: - Height of the classroom: 3.5 m - Length of the classroom: 13 m - Width of the classroom: 5.5 m - Initial concentration of bacteria: 2600 bacteria per cubic meter

To find the volume of the classroom, we multiply the height, length, and width: Volume of the classroom = Height * Length * Width

Substituting the given values: Volume of the classroom = 3.5 m * 13 m * 5.5 m = 254.25 cubic meters

Now, we can calculate the number of bacteria in the classroom before the lessons: Number of bacteria in the classroom before the lessons = Volume of the classroom * Initial concentration of bacteria

Substituting the values: Number of bacteria in the classroom before the lessons = 254.25 cubic meters * 2600 bacteria per cubic meter = 661,650 bacteria

Therefore, there are approximately 661,650 bacteria in the classroom before the lessons.

2) Сколько бактерий в классе после 4-ех уроков, если класс не проветривается?

To calculate the number of bacteria in the classroom after 4 lessons without ventilation, we need to consider the increase in bacteria concentration after each lesson.

Given: - Increase in bacteria concentration after 2 lessons: 13500 bacteria per cubic meter - Increase in bacteria concentration after each lesson: 13500 bacteria per cubic meter

After 4 lessons, the number of bacteria in the classroom would be: Number of bacteria in the classroom after 4 lessons = Number of bacteria in the classroom before the lessons + (Increase in bacteria concentration after 2 lessons * 2)

Substituting the values: Number of bacteria in the classroom after 4 lessons = 661,650 bacteria + (13500 bacteria per cubic meter * 2) = 688,650 bacteria

Therefore, there would be approximately 688,650 bacteria in the classroom after 4 lessons without ventilation.

3) Сколько бактерий в классе после 7-ми уроков, если класс не проветривается?

To calculate the number of bacteria in the classroom after 7 lessons without ventilation, we need to consider the increase in bacteria concentration after each lesson.

Given: - Increase in bacteria concentration after each lesson: 13500 bacteria per cubic meter

After 7 lessons, the number of bacteria in the classroom would be: Number of bacteria in the classroom after 7 lessons = Number of bacteria in the classroom before the lessons + (Increase in bacteria concentration after 2 lessons * 3) + (Increase in bacteria concentration after each lesson * 2)

Substituting the values: Number of bacteria in the classroom after 7 lessons = 661,650 bacteria + (13500 bacteria per cubic meter * 3) + (13500 bacteria per cubic meter * 2) = 826,650 bacteria

Therefore, there would be approximately 826,650 bacteria in the classroom after 7 lessons without ventilation.

4) Сколько бактерий в классе будет после 4-ех и 7-ми уроков, если перед изменением помещение проветривается?

If the classroom is ventilated before the change, the number of bacteria would be reduced by 3 times.

To calculate the number of bacteria in the classroom after 4 and 7 lessons with ventilation, we need to consider the reduction in bacteria concentration after ventilation.

Given: - Reduction in bacteria concentration after ventilation: 3 times

After ventilation, the number of bacteria in the classroom would be: Number of bacteria in the classroom after ventilation = (Number of bacteria in the classroom before the lessons + (Increase in bacteria concentration after 2 lessons * 2) + (Increase in bacteria concentration after each lesson * 2)) / 3

Substituting the values: Number of bacteria in the classroom after ventilation = (661,650 bacteria + (13500 bacteria per cubic meter * 2) + (13500 bacteria per cubic meter * 2)) / 3 = 229,550 bacteria

Therefore, there would be approximately 229,550 bacteria in the classroom after 4 and 7 lessons with ventilation.

Please note that these calculations are based on the given information and assumptions. The actual number of bacteria in a specific classroom may vary depending on various factors.