The mowing speed is 1.5 m / s. The average blade speed of the mower in one stroke is 1.8 m / s.

The mowing speed is 1.5 m / s. The average blade speed of the mower in one stroke is 1.8 m / s. Find the speed of the knife relative to the meadow if the movement of the knife is perpendicular to the direction of movement of the mower.

The speed of the knife relative to the meadow V can be found by adding the velocity vectors of the mower Vк and the knife Vн.
Addition: at the end of the mower velocity vector Vk, place the beginning of the knife velocity vector Vn. Connect the beginning of the Vk vector with the end of the Vн vector. A right-angled triangle is formed, in which the legs will be the velocities, and the hypotenuse will be equal to the sum of the vectors V.
V2 = Vk2 + Vk2;
V = √ (Vk2 + Vn2) = √ ((1.5 m / s) 2 + (1.8 m / s) 2) = 2.34 m / s.
Answer: 2.34 m / s.