The train, 10 seconds after the start of movement, acquires a speed of 2.6 m / s. After what time from the beginning

The train, 10 seconds after the start of movement, acquires a speed of 2.6 m / s. After what time from the beginning of movement the speed will be equal to 30 m / s? Consider the movement uniformly accelerated.

Assuming the initial speed to be zero, we find the acceleration of the train:

a = v1 / t1 = 2.6 / 10 = 0.26 m / s2;

Let us find the time t2 for which the train will accelerate to 30 m / s:

t2 = v2 / a = 30 / 0.26 = 115.4 s.

Answer: 115.4 seconds after the start of movement, the train will pick up a speed of 30 m / s.