The car drove through the first section of the route at a speed of 11 km / h, and the second at a speed of 40 km / h

| June 21, 2021 | education

The car drove through the first section of the route at a speed of 11 km / h, and the second at a speed of 40 km / h, and it took the same time to pass each of the sections. What is the average speed all the way?

V1 = 11 km / h.

V2 = 40 km / h.

t1 = t2.

Vav -?

To find the average vehicle speed Vav, it is necessary to divide the entire path S it has traveled by the time of its movement t: Vav = S / t.

The entire path S traveled by him will be the sum: S = S1 + S2, where S1 is the distance of the first section of the path, S2 is the distance of the second section of the path.

S1 = V1 * t1.

S2 = V2 * t2 = V2 * t1.

S = V1 * t1 + V2 * t1 = (V1 + V2) * t1.

The travel time of the entire path is expressed by the sum: t = t1 + t2, where t1 is the time of movement on the first section of the path, t2 is the time of movement on the second section of the path.

Since t1 = t2, then t = t1 + t1 = 2 * t1.

Vav = (V1 + V2) * t1 / 2 * t1 = (V1 + V2) / 2.

Vav = (11 km / h + 40 km / h) / 2 = 25.5 km / h.

Answer: the average vehicle speed was Vav = 25.5 km / h.



One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.