Question

Два поезда идут навстречу друг другу по двум параллельным путям со скоростью 36 и 54 км/ч. Длины поездов 120 и 150м. Определите время,в течение которого поезда проходят мимо друг друга. С каким телом вы связали систему координат? С каким ещё тело можно связать систему координатP.s желательно решение сделайте на листочкеЗарание спасибо)0)

Answer 1

36 км.ч = 10м.с
54 км.ч = 15м.с
раз они идут навстречу скорости складываются
15+10=25 м.с
Их общая длина, которую они должны будут проехать равна :
120+150 = 270 м
Теперь найдем за какое время они проедут эту дистанцию, мысленно остановим 1 поезд и другом передадим всю скорость 25м.с
270м/ 25 = 10.8 с .  Время за которое они проходят мимо друг друга.
Система координат была связана с поездом имеющим наибольшую скорость и длину.

Answer 2

Problem Statement

Two trains are traveling towards each other on parallel tracks. The first train has a speed of 36 km/h and a length of 120 meters, while the second train has a speed of 54 km/h and a length of 150 meters. We need to determine the time it takes for the trains to pass each other. Additionally, we need to determine the body with which we can associate the coordinate system and another body that can be associated with the coordinate system.

Solution

To find the time it takes for the trains to pass each other, we can use the concept of relative velocity. The relative velocity is the difference between the velocities of the two trains. Let's calculate the relative velocity first.

The relative velocity of the second train with respect to the first train is given by: Relative velocity = Velocity of the second train - Velocity of the first train

Using the given values, we can calculate the relative velocity: Relative velocity = 54 km/h - 36 km/h = 18 km/h Now, let's convert the relative velocity to meters per second (m/s) for consistency: Relative velocity = 18 km/h * (1000 m/1 km) * (1 h/3600 s) = 5 m/s

The total distance the trains need to cover to pass each other is the sum of their lengths: Total distance = Length of the first train + Length of the second train Total distance = 120 meters + 150 meters = 270 meters

To find the time it takes for the trains to pass each other, we can use the formula: Time = Distance / Relative velocity

Substituting the values, we get: Time = 270 meters / 5 m/s = 54 seconds

Therefore, the trains will pass each other in 54 seconds.

Coordinate System

To determine the body with which we can associate the coordinate system, we need to consider the motion of the trains. Since the trains are moving towards each other on parallel tracks, we can associate the coordinate system with either train.

Let's associate the coordinate system with the first train. In this case, the first train will be at the origin of the coordinate system, and the second train will have a negative position relative to the first train.

Alternatively, we can associate the coordinate system with the second train. In this case, the second train will be at the origin of the coordinate system, and the first train will have a positive position relative to the second train.

Both choices are valid, and the selection depends on the convenience and context of the problem.

In summary, the time it takes for the trains to pass each other is 54 seconds. The coordinate system can be associated with either train, depending on the convenience and context of the problem.

I hope this helps! Let me know if you have any further questions.