Question

При приближении к станции модуль скорости движения локомотива изменился от V1=72км/ч до нуля за промежуток времени ∆t=1,5 мин..Определите модуль ускорения локомотива.Куда было направлено ускорение?

Answer 1

А=-20/90=-2,(2)м/с^2; направлено против вектора скорости

Answer 2

Calculation of Acceleration and Direction

To determine the acceleration of the locomotive and its direction, we can use the given information about the change in velocity and the time interval.

The initial velocity of the locomotive, V1, is 72 km/h, and it changes to zero within a time interval of ∆t = 1.5 minutes.

To calculate the acceleration, we can use the formula:

Acceleration (a) = Change in velocity (Δv) / Time interval (Δt)

Substituting the given values:

Acceleration (a) = (0 - 72 km/h) / (1.5 minutes)

Now, let's convert the time interval from minutes to hours to match the units of velocity:

Acceleration (a) = (0 - 72 km/h) / (1.5/60 hours)

Simplifying the expression:

Acceleration (a) = (0 - 72 km/h) / (0.025 hours)

Acceleration (a) = -2880 km/h^2

Therefore, the magnitude of the acceleration of the locomotive is 2880 km/h^2. The negative sign indicates that the locomotive is decelerating or slowing down.

As for the direction of the acceleration, since the velocity is decreasing from 72 km/h to zero, the acceleration is directed opposite to the initial velocity. In this case, the acceleration is directed in the opposite direction of the locomotive's motion.

Please note that the units used in this calculation are consistent with the given values. However, it is important to convert the units appropriately when performing calculations to ensure consistency.