The body moves in accordance with the equation x = (5 + 8t) m. Determine the speed of this body in 3 s.

From this equation it can be seen that the movement is uniform rectilinear, the initial coordinate is 5m. Because the motion is uniform and rectilinear, then the speed will be the same even after 3, even after 10, even after 9999 m. From the equation of motion: V = 8m / s
Answer: V = 8m / s

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