Respostas

2014-02-15T16:48:25-02:00
Resposta

72km/h = 20m/s
S = 50m

V² = Vi² + 2a.S
0² = 20² + 2a.50
0 = 400 + 100a
100a = -400
a = -400/100
a = -4m/s²

Modulo

a = 4m/s²
3 4 3