# An athlete, moving at a constant speed, runs through the stadium in n-2 circles with a radius of R = 20m.

**An athlete, moving at a constant speed, runs through the stadium in n-2 circles with a radius of R = 20m. Find the path s and the movement module delta r of the athlete.**

n = 2.

R = 20 m.

L -?

S -?

The traversed path L is the length of the trajectory that the athlete describes when moving.

The circumference is determined by the formula: L1 = 2 * П * R, where P is the number pi, R is the radius of the circle.

Since the athlete makes n circles, he goes the path L = n * L1 = n * 2 * П * R.

L = 2 * 2 * 3.14 * 20 m = 251.2 m.

The movement of the athlete S is called the vector that connects the starting and ending position of the body. The modulus of displacement S is the length of this vector.

Since the athlete makes n = 2 an integer number of revolutions, he returns to his initial position. The athlete’s starting and ending positions are the same, so S = 0.

Answer: the athlete’s path was L = 251.2 m, displacement S = 0.