A body weighing 0.5 kg moves according to the law x = -3 + 4t-5t ^ 2.

A body weighing 0.5 kg moves according to the law x = -3 + 4t-5t ^ 2. Determine the impulse of the body 2 seconds after the start of the movement.

Initial data: m (body weight) = 0.5 kg; the law of motion: x (t) = -3 + 4t – 5t ^ 2; t (considered travel time) = 2 s.

1) The law of speed change: V (t) = x (t) ‘= (-3 + 4t – 5t ^ 2)’ = -0 + 4 * 1 – 5 * 2t = 4 – 10t.

2) The impulse of a given body after 2 seconds: P (2) = m * V (2) = 0.5 * (4 – 10 * 2) = -8 kg * m / s.

Answer: After 2 seconds, the modulus of the impulse of the given body will be equal to 8 kg * m / s.