Respostas

2014-08-18T21:46:26-03:00
A)F=k.x
F=800n
k=?
x=0,2m
k=F/x
k=800/0,2
k=4000n/m

b)Epel=k.x²/2
Epel=4000.0,2²/2
Epel=4000.0,04/2
Epel=2000.0,04
Epel=80J

c)F=?
k=4000n/m
x=2.0,2=0,4m
F=4000.0,4
F=1600N