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## Homework Statement

A spring with spring constant k = 55 N/m and unstretched length of L0 is attached to the ceiling. A block of mass m = 3 kg is hung gently on the end of the spring.

a) How far does the spring stretch?

----------ANSWER: .53509 m

This is the hard part...

**Now the block is pulled down until the total amount the spring is stretched is

**twice**the amount found in part (a). The block is then pushed upward with an initial speed vi = 2 m/s.

## Homework Equations

KE = (1/2) mv^2

KE = (1/2) kx^2

KE + PE = 0

## The Attempt at a Solution

I tried simply doubling the distance found in part a to get

__, and then plugged that into the formula KE = 1/2 kx^2 to get__

**x=1.07018****.**

__KE = 31.495__I then used that value in KE = 1/2 mv^2 and solved for v to get

__, which is wrong. I also tried to add 2 to that to get__

**v=4.58**__, but thats wrong too.__

**v=6.58**How do I incorporate the Vi = 2 into this?