- #1

Suraj M

Gold Member

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## Homework Statement

A block of mass 250 g is kept on a vertical spring with spring constant 100N/m fixed from below.

The spring is now compressed to have a length 10 cm shorter than its natural length and is released. How high does the block rise?g = 10m/s

## Homework Equations

E=½kx²

and other basic equations

## The Attempt at a Solution

So I found out initial energy imparted,

$$E_1 = ½kx² = 0.5 J$$

then equated to change in potential and new spring energy.

$$E_2 = mgh + ½k(x-h)²$$ where h is the height required

solving E₁= E₂, I get an awkward answer. the answer given is 20 cm. How?