Respostas

2013-10-15T22:54:19-03:00
2013-10-16T00:02:25-03:00
A)
Fr² = 12² + 16²
Fr² = 144 + 256
Fr² = 400
Fr = 20N  
b)
a = F/m
a = 20/4
a = 5 m/s² 
2 5 2