(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A horizontal spring, of force constant 12 N/m is mounted at the edge of a lab bench to shoot marbles at targets on the floor 93.0 cm below. A marble of mass 8.3 X 10 ^ -3 kg is shot from the spring, which is initially compressed a distance of 4.0 cm. How far does the marble travel horizontally before hitting the floor?

2. Relevant equations

E-elastic = 1/2kx^2

E-gravity = mgy

E-kinetic = 1/2mv^2

3. The attempt at a solution

The given information:

m = 8.3 X 10 ^ -3 kg

k = 12 N/m

x = 4.0 cm --> 0.04 m

delta Y = 93 cm --> 0.93 m

In the start, the elastic energy and the kinetic energy should be the same. So for some reason, I think I have to find the velocity.

Ee = Ek

1/2kx^2 = 1/2mv^2

1/2 (12) (0.04)^2 = 1/2 (8.3 X 10 ^ -3)v^2

0.0096 = 0.00415 X v^2

v^2 = 2.31

v= 1.52 m/s

So now that I have velocity, I think I can find the horizontal distance.

But I don't know what to do now. Can anyone please help me? Thanks.

IMPORTANT NOTE:

Our teacher told us that we cannot use the equation delta X = vi^2 / g X sin2theta. So please anyone help me in doing in this question without the use of this projectile motion equation.

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# Homework Help: Elastic Potential Energy of a marble

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