Question

a dart of mass 0.100 kg is pressed against the spring of a toy dart gun. The spring (with spring stiffness constant k = 250 N/m and ignorable mass) is compress 6.0 cm and realeased. if the dart detaches from the spring when the spring reaches its natural length (x=0), what speed does the dart acquirep

Answer 1

Uk : elastic potential energy
Ek : kinetic energy
Uk = Ek
1/2 x k x X^2 = 1/2 x m x V^2
1/2 x 250 x 0.06^2 = 1/2 x 0.1 x V^2
V = 3 m/s