Respostas

2013-11-20T23:49:01-02:00
Ec =mv2/2
a)
m=10Kg
v=5m/s
Ec= 10x5x5/2
Ec=125j

b) 125=1/4xv2/2
250=0,25xv2
v2=250/0,25
v=raiz quadrada de 1000
v=31,6m/s