Answer:
v = 3.65 m / s
Explanation:
In this exercise we use the conservation of mechanical energy
starting point. Point A compressed spring
Em₀ = 100 J
final point. Point B uncompressed spring
Em_f = K = ½ m v²
energy is conserved
Em₀ = Em₀_f
100 = ½ m v²
v = [tex]\sqrt{ \frac{2 \ 100 }{m} }[/tex]
v = [tex]\sqrt {200/15}[/tex]
v = 3.65 m / s