A body weighing 400 g moves rectilinearly under the action of a force of 0.6 N.

A body weighing 400 g moves rectilinearly under the action of a force of 0.6 N. What initial velocity did the body have if the modulus of displacement in 5 s is 31.25 m?

To find the initial speed of movement of a given body, we apply the formula: S = Vn * t + a * t ^ 2/2, whence we express: Vn = (S – a * t2 / 2) / t = (S – F * t ^ 2 / 2m) / t.

Variables: S – displacement modulus (S = 31.25 m); F – acting force (F = 0.6 N); t – movement time (t = 5 s); m – body weight (m = 400 g = 0.4 kg).

Calculation: Vн = (S – F * t ^ 2 / 2m) / t = (31.25 – 0.6 * 5 ^ 2 / (2 * 0.4)) / 5 = 2.5 m / s.

Answer: The body had an initial velocity of 2.5 m / s.



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