How Is Maximum Elongation Calculated in a Spring System?

[MathewsMD]

A 2-kg block is attached to a horizonal ideal spring with a spring constant of 200 N/m. When the spring has its equilibrium length the block is given a speed of 5 m/s. What is the maximum elongation of the spring?

Is not the solution simply:

1/2kx² = 1/2mv²

x = (mv²/k)^0.5

x = 0.5 m?

That is incorrect, though.

 

[Doc Al]

Looks correct to me.

 

[rude man]

Me too.

 

[MathewsMD]

The answer was 5m...probably a typo, just wanted to confirm.

Thanks.