Answer to Question #79393 in Physics for xii

Question

A vertical spring (ignore its mass)<, whose spring stiffness constant is 950 Nm-1, is attached to a table and is compressed down 0.150m.
a) What upward speed can it give to a 0.30 kg ball when released?
b) How high above its original position (spring compressed) will the ball fly?

Answer 1

a) From the conservation of energy:
(mv^2)/2=(kx^2)/2
v=x√(k/m)=0.150√(950/0.30)=8.4 m/s.
b) From the conservation of energy:
mgh=(mv^2)/2=(kx^2)/2
h=(kx^2)/2mg=((950) (0.150)^2)/(2(0.30)(9.8))=3.6 m.