The train went for one hour at a speed of 20 m / s, then for another 3 hours at a speed of 36
The train went for one hour at a speed of 20 m / s, then for another 3 hours at a speed of 36 km / h, and the length of the last section of the track was 20 km. What was the train route?
t1 = 1 h = 3600 s.
V1 = 20 m / s.
t2 = 3 h = 10800 s.
V2 = 36 km / h = 10 m / s.
S3 = 20 km = 20,000 m.
S -?
The entire path S traveled by the train will be the sum: S = S1 + S2 + S3.
The path S traveled by the train with uniform rectilinear movement is determined by the formula: S = V * t, where V is the speed of movement, t is the time of movement.
The traversed path on the first part of the path S1 is expressed by the formula: S1 = V1 * t1.
The traversed path on the second part of the path S2 is expressed by the formula: S2 = V2 * t2.
S = V1 * t1 + V2 * t2 + S3.
S = 20 m / s * 3600 s + 10 m / s * 10800 s + 20,000 m = 200,000 m = 200 km.
Answer: the train traveled the path S = 200,000 m = 200 km.