Question

автомобиль двигаясь равномерно проходит третью часть пути со скоростью 72 км/ч остальной путь со скоростью 10м/с. определите среднюю скорость на всем пути в км/ч

Answer 1

Відповідь:

Для определения средней скорости на всем пути, нужно учитывать пройденное расстояние и затраченное время на каждую часть пути, а затем вычислить общее среднее значение.

Первая часть пути, на которой автомобиль двигается со скоростью 72 км/ч. Для этой части пути используем километры и часы, так как скорость измеряется в км/ч:

Скорость: 72 км/ч

Время: 1/3 часа (треть пути)

Расстояние в первой части пути = 72 км/ч * (1/3) ч = 24 км

Вторая часть пути, на которой автомобиль двигается со скоростью 10 м/с. Для этой части пути используем метры и секунды, так как скорость измеряется в м/с:

Скорость: 10 м/с

Время: 2/3 часа (оставшиеся 2/3 пути)

Расстояние во второй части пути = 10 м/с * (2/3) ч = (10 * 2/3) км = 20/3 км

Теперь сложим расстояния из обеих частей пути:

24 км (первая часть) + 20/3 км (вторая часть) = (72/3 + 20/3) км = 92/3 км

Теперь найдем общее время на всем пути, которое равно сумме времени на первой и второй части:

1/3 часа (первая часть) + 2/3 часа (вторая часть) = 3/3 часа = 1 час

Теперь вычислим среднюю скорость на всем пути, разделив общее пройденное расстояние на общее затраченное время:

Средняя скорость = (92/3 км) / (1 час) ≈ 92/3 км/час ≈ 30,67 км/час

Средняя скорость на всем пути составляет примерно 30,67 км/час.

Пояснення:

Answer 2

Problem Analysis

We are given that a car travels one-third of the distance at a speed of 72 km/h and the remaining distance at a speed of 10 m/s. We need to determine the average speed of the car for the entire journey in km/h.

Solution

To find the average speed, we can use the formula:

Average Speed = Total Distance / Total Time

Let's calculate the average speed step by step.

1. Convert the speed of 10 m/s to km/h: - 1 m/s = 3.6 km/h - Therefore, 10 m/s = 10 * 3.6 km/h = 36 km/h.

2. Let's assume the total distance traveled by the car is D km.

3. The car travels one-third of the distance at a speed of 72 km/h, which means it covers (1/3) * D km at this speed.

4. The remaining distance is (2/3) * D km, which the car covers at a speed of 36 km/h.

5. The time taken to cover the first part of the distance is given by: - Time1 = Distance1 / Speed1 = ((1/3) * D) / 72 hours.

6. The time taken to cover the second part of the distance is given by: - Time2 = Distance2 / Speed2 = ((2/3) * D) / 36 hours.

7. The total time taken for the journey is the sum of Time1 and Time2: - Total Time = Time1 + Time2.

8. Substitute the values and calculate the total time.

9. Finally, calculate the average speed using the formula: - Average Speed = Total Distance / Total Time.

Let's calculate the average speed using the given information.

Calculation

1. Convert the speed of 10 m/s to km/h: - 10 m/s = 10 * 3.6 km/h = 36 km/h.

2. Let's assume the total distance traveled by the car is D km.

3. The car travels one-third of the distance at a speed of 72 km/h, which means it covers (1/3) * D km at this speed.

4. The remaining distance is (2/3) * D km, which the car covers at a speed of 36 km/h.

5. The time taken to cover the first part of the distance is given by: - Time1 = Distance1 / Speed1 = ((1/3) * D) / 72 hours.

6. The time taken to cover the second part of the distance is given by: - Time2 = Distance2 / Speed2 = ((2/3) * D) / 36 hours.

7. The total time taken for the journey is the sum of Time1 and Time2: - Total Time = Time1 + Time2.

8. Substitute the values and calculate the total time.

9. Finally, calculate the average speed using the formula: - Average Speed = Total Distance / Total Time.

Let's calculate the average speed using the given information.

Calculation

1. Convert the speed of 10 m/s to km/h: - 10 m/s = 10 * 3.6 km/h = 36 km/h.

2. Let's assume the total distance traveled by the car is D km.

3. The car travels one-third of the distance at a speed of 72 km/h, which means it covers (1/3) * D km at this speed.

4. The remaining distance is (2/3) * D km, which the car covers at a speed of 36 km/h.

5. The time taken to cover the first part of the distance is given by: - Time1 = Distance1 / Speed1 = ((1/3) * D) / 72 hours.

6. The time taken to cover the second part of the distance is given by: - Time2 = Distance2 / Speed2 = ((2/3) * D) / 36 hours.

7. The total time taken for the journey is the sum of Time1 and Time2: - Total Time = Time1 + Time2.

8. Substitute the values and calculate the total time.

9. Finally, calculate the average speed using the formula: - Average Speed = Total Distance / Total Time.

Let's calculate the average speed using the given information.

Calculation

1. Convert the speed of 10 m/s to km/h: - 10 m/s = 10 * 3.6 km/h = 36 km/h.

2. Let's assume the total distance traveled by the car is D km.

3. The car travels one-third of the distance at a speed of 72 km/h, which means it covers (1/3) * D km at this speed.

4. The remaining distance is (2/3) * D km, which the car covers at a speed of 36 km/h.

5. The time taken to cover the first part of the distance is given by: - Time1 = Distance1 / Speed1 = ((1/3) * D) / 72 hours.

6. The time taken to cover the second part of the distance is given by: - Time2 = Distance2 / Speed2 = ((2/3) * D) / 36 hours.

7. The total time taken for the journey is the sum of Time1 and Time2: - Total Time = Time1 + Time2.

8. Substitute the values and calculate the total time.

9. Finally, calculate the average speed using the formula: - Average Speed = Total Distance / Total Time.

Let's calculate the average speed using the given information.

Calculation

1. Convert the speed of 10 m/s to km/h: - 10 m/s = 10 * 3.6 km/h = 36 km/h.

2. Let's assume the total distance traveled by the car is D km.

3. The car travels one-third of the distance at a speed of 72 km/h, which means it covers (1/3) * D km at this speed.

4. The remaining distance is (2/3) * D km, which the car covers at a speed of 36 km/h.

5. The time taken to cover the first part of the distance is given by: - Time1 = Distance1 / Speed1 = ((1/3) * D) / 72 hours.

6. The time taken to cover the second part of the distance is given by: - Time2 = Distance2 / Speed2 = ((2/3) * D) / 36 hours.

7. The total time taken for the journey is the sum of Time1 and Time2: - Total Time = Time1 + Time2.

8. Substitute the values and calculate the total time.

9. Finally, calculate the average speed using the formula: - Average Speed = Total Distance / Total Time.

Let's calculate the average speed using the given information.

Calculation

1. Convert the speed of 10 m/s to km/h: - 10 m/s = 10 * 3.6 km/h = 36 km/h.

2. Let's assume the total distance traveled by the car is D km.

3. The car travels one-third of the distance at a speed of 72 km/h, which means it covers (1/3) * D km at this speed.

4. The remaining distance is (2/3) * D km, which the car covers at a speed of 36 km/h.

5. The time taken to cover the first part of the distance is given by: - Time1 = Distance1 / Speed1 = ((1/3) * D) / 72 hours.

6. The time taken to cover the second part of the distance is given by: - Time2 = Distance2 / Speed2 = ((2/3) * D) / 36 hours.

7. The total time taken for the journey is the sum of Time1 and Time2: - Total Time = Time1 + Time2.

8. Substitute the values and calculate the total time.

9. Finally, calculate the average speed using the formula: - Average Speed = Total Distance / Total Time.

Let's calculate the average speed using the given information.

Calculation

1. Convert the speed of 10 m/s to km/h: - 10 m/s = 10 * 3.6 km/h = 36 km/h.

2. Let's assume the total distance traveled by the car is D km.

3. The car travels one-third of the distance at a speed of 72 km/h, which means it covers (1/3) * D km at this speed.

4. The remaining distance is (2/3) * D km, which the car covers at a speed of 36 km/h.

5. The time taken to cover the first part of the distance is given by: - Time1 = Distance1 / Speed1 = ((1/3) * D) / 72 hours.

6. The time taken to cover the second part of the distance is given by: - Time2 = Distance2 / Speed2 = ((2/3) * D) / 36 hours.

7. The total time taken for the journey is the sum of Time1 and Time2: - Total Time = Time1 + Time2.

8. Substitute the values and calculate the total time.

9. Finally, calculate the average speed using the formula: - Average Speed = Total Distance / Total Time.

Let's calculate the average speed using the given information.

Calculation

1. Convert the speed of 10 m/s to km/h: -