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rum2563
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Homework Statement
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?
Homework Equations
E-elastic = 1/2kx^2
E-gravity = mgy
E-kinetic = 1/2mv^2
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.