Question

Поезд, дви­га­ясь рав­но­мер­но со ско­ро­стью 66 км/ч, про­ез­жа­ет мимо пе­ше­хо­да, иду­ще­го па­рал­лель­но путям со ско­ро­стью 3 км/ч нав­стре­чу по­ез­ду, за 57 се­кунд. Най­ди­те длину по­ез­да в мет­рах.

Answer 1

Ответ:

Пошаговое объяснение:

Встречная скорость 66 + 3 = 69 км/час

57 сек в часах,   57/60*60 = 0,01583 часа

Длина поезда  69 км/час *  0,01583 час = 1,0925 км = 1092,5 метра

Answer 2

Problem Analysis

We are given that a train is moving at a constant speed of 66 km/h and passes a pedestrian who is walking parallel to the tracks at a speed of 3 km/h in the opposite direction. We need to find the length of the train in meters.

Solution

To find the length of the train, we can use the relative speed of the train and the pedestrian. The relative speed is the sum of their individual speeds.

Let's assume the length of the train is 'x' meters.

The relative speed of the train and the pedestrian is the speed at which the train approaches the pedestrian. It is given by the sum of their speeds, which is 66 km/h + 3 km/h = 69 km/h.

We need to convert this relative speed from km/h to m/s, as the time given is in seconds. To convert km/h to m/s, we divide by 3.6 (1 km/h = 1000 m/3600 s = 1/3.6 m/s).

So, the relative speed is (69 km/h) / (3.6 m/s) = 19.17 m/s.

We are given that the train passes the pedestrian in 57 seconds. We can use the formula:

Distance = Speed × Time

The distance covered by the train in 57 seconds is equal to the length of the train.

Therefore, we have:

x = (19.17 m/s) × (57 s)

Now we can calculate the length of the train.

Calculation

Let's calculate the length of the train using the given values:

x = (19.17 m/s) × (57 s)

x = 1094.69 meters

Answer

The length of the train is 1094.69 meters.

Explanation

When a train passes a stationary object, the distance covered by the train in a given time is equal to the length of the train. In this case, the train passes the pedestrian in 57 seconds, so the distance covered by the train in 57 seconds is equal to the length of the train. By calculating the distance using the formula Distance = Speed × Time, we find that the length of the train is 1094.69 meters.