Letra A)
S = So + vot + at²/2
20 = 0 + 0t + a*4² / 2
20 = 8 a
20/8 = a
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a = 2,5m/s²
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Fr = m * a
Fr = 5 * 2,5
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Fr = 12,5N (Força resultante)
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Letra B)
S = So + Vot + at²/2
S = 0 + 0t + 2,5 * 30² / 2
S = 2,5 * 900 / 2
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S = 1125 metros // Distancia percorrida
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