Question

поезд отошел от платформы со скоростью 80м/мин. затем разогнался и увеличил скорость в 15 раз. какую скорость набрал поезд в пути. Выразите ее в километрах в час

Answer 1

80 * 15 = 1200 м/мин

1200 * 60 / 1000 = 72 км/час

Answer 2

80*15=1,2км/ч ....ну вот так!)

 

Answer 3

Calculation of the Train's Speed

To calculate the speed of the train, we need to consider two stages: when the train departs from the platform and when it accelerates.

1. Stage 1: Departure from the platform - The train departs from the platform with a speed of 80 m/min. - To convert this speed to km/h, we need to multiply it by 60 (to convert minutes to hours) and divide by 1000 (to convert meters to kilometers). - Therefore, the speed of the train during the departure from the platform is 80 * 60 / 1000 = 4.8 km/h.

2. Stage 2: Acceleration - After departing from the platform, the train accelerates and increases its speed by 15 times. - Let's assume the initial speed after departure is V km/h. - The final speed after acceleration is 15V km/h. - We need to find the value of V.

To find V, we can use the following equation:

15V = 80 * 60 / 1000

Simplifying the equation:

V = (80 * 60 / 1000) / 15

Calculating V:

V = 4.8 / 15

V ≈ 0.32 km/h

Therefore, the initial speed of the train after departing from the platform is approximately 0.32 km/h.

The final speed of the train in the journey is 15 times the initial speed:

Final speed = 15 * 0.32 km/h

Final speed ≈ 4.8 km/h

So, the train reaches a speed of approximately 4.8 km/h during its journey.