Question

Електричка проходить шлях між двома станціями за 40 хв. При цьому 10 хв із них вона витрачає на розгін і гальмування, а 30 хв — на рівномірний рух зі швидкістю 90 км/год. Знайдіть відстань між станціями. Вважайте, що швидкість електрички при розгоні та гальмуванні з часом змінювалась лінійно.​

Answer 1

в цій задачі 25 хв всёго за 40

Answer 2

To find the distance between the two stations, we can use the formula:

Distance = (Initial Velocity + Final Velocity) / 2 * Time

Given that the train spends 10 minutes on acceleration and deceleration, and 30 minutes on uniform motion at a speed of 90 km/h, we can calculate the distance.

Calculation:

1. Convert the time spent on acceleration and deceleration to hours: - 10 minutes = 10/60 = 1/6 hour

2. Calculate the average velocity during acceleration and deceleration: - Initial velocity = 0 km/h (since the train starts from rest) - Final velocity = 90 km/h - Average velocity = (Initial velocity + Final velocity) / 2 = (0 + 90) / 2 = 45 km/h

3. Calculate the distance covered during acceleration and deceleration: - Distance = Average velocity * Time = 45 km/h * (1/6) hour = 7.5 km

4. Calculate the distance covered during uniform motion: - Speed = 90 km/h - Time = 30 minutes = 30/60 = 1/2 hour - Distance = Speed * Time = 90 km/h * (1/2) hour = 45 km

5. Calculate the total distance between the two stations: - Total distance = Distance during acceleration/deceleration + Distance during uniform motion = 7.5 km + 45 km = 52.5 km

Therefore, the distance between the two stations is 52.5 kilometers.