Question

Помогите решить задачу по физике! Поезд прошёл путь s=6 км между двумя станциями со средней путевой скоростью 60км/ч. При этом на разгон в начале движения и торможения в конце он затратил 4мин, а остальное время двигался с постоянной скоростью. Чему равна эта скорость?

Answer 1

Problem Analysis

To solve this problem, we need to find the speed at which the train was moving between the two stations. We are given that the train traveled a distance of 6 km with an average speed of 60 km/h. Additionally, the train spent 4 minutes on acceleration at the beginning and deceleration at the end of the journey, while the rest of the time it traveled at a constant speed.

Solution

Let's break down the problem into steps to find the solution:

1. Convert the time spent on acceleration and deceleration to hours. - We are given that the train spent 4 minutes on acceleration and deceleration. - There are 60 minutes in an hour, so 4 minutes is equal to 4/60 = 0.067 hours.

2. Calculate the time spent traveling at a constant speed. - The total time of the journey is the time spent on acceleration and deceleration plus the time spent traveling at a constant speed. - The total time is equal to the time spent on acceleration and deceleration plus the time spent traveling at a constant speed. - Let's denote the time spent traveling at a constant speed as t. - The total time is given by the equation: t + 0.067 = total time.

3. Calculate the time spent traveling at a constant speed in hours. - The total time is given as 6 km / 60 km/h = 0.1 hours. - Substituting this value into the equation from step 2, we get: t + 0.067 = 0.1. - Solving for t, we find that t = 0.1 - 0.067 = 0.033 hours.

4. Calculate the speed at which the train was moving between the two stations. - The speed is equal to the distance traveled divided by the time spent traveling at a constant speed. - The speed is given by the equation: speed = distance / time. - Substituting the values, we get: speed = 6 km / 0.033 hours.

Calculation

Let's calculate the speed of the train:

speed = 6 km / 0.033 hours = 181.82 km/h.

Therefore, the speed of the train between the two stations is approximately 181.82 km/h.

Please note that the above solution assumes that the train accelerates and decelerates uniformly during the given time.