Answer:
v = 9.43 m/s
Explanation:
According to Hooke's law;
F = kx ------------- eqn 1
where F = spring force = 80 N
k = spring constant = ?
x = spring stretch = 0.200 m
substitute for F and x to find k
80 = 0.2k
[tex]k = \frac{80}{0.2} = 400 N/m[/tex]
[tex]\frac{1}{2} kx^{2} = \frac{1}{2} mv^{2}[/tex]
[tex]\frac{1}{2}X400X0.2^{2} = \frac{1}{2}X 0.18v^{2}[/tex]
[tex]200 X 0.04 = 0.09v^2[/tex]
[tex]8 = 0.09v^2[/tex]
[tex]v^2 = \frac{8}{0.09}[/tex]
[tex]v^2 = 88.89[/tex]
[tex]v = \sqrt{88.89}[/tex]
[tex]v = 9.43m/s[/tex]
