What is the equation for a spring launcher?

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The discussion centers on finding the correct equation for a spring launcher, specifically how to incorporate the angle of launch. The user initially presents an equation for potential energy but struggles with its accuracy and the inclusion of launch angle. They propose a revised equation relating spring potential energy to gravitational work and kinetic energy. Feedback indicates that their latest attempt appears correct. The conversation highlights the need for clarity in applying physics principles to solve the problem.
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Homework Statement
What is the generalized equation of the initial launch speed for a spring launcher at different angles? Use PE of the spring, mass, and angle in the equation.
Relevant Equations
Ei = Ef
PEspring = 1/2 kx^2
KE = 1/2 mv^2
I am really stuck and confused. I just need the equation. Thanks!

Here is my attempt at solving:

PEspring = 1/2m(Vx^2 +Vy^2)
 
Last edited:
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Riman643 said:
Problem Statement: What is the generalized equation of the initial launch speed for a spring launcher at different angles? Use PE of the spring, mass, and angle in the equation.
Relevant Equations: Ei = Ef
PEspring = 1/2 kx^2
KE = 1/2 mv^2

I am really stuck and confused. I just need the equation. Thanks!
What have is your assessment so far?
 
This is my attempt

PEspring = 1/2m(Vx^2 +Vy^2). I know this is not right. I am confused and have been trying to figure this out for two days now. I do not know how to incorporate the angle of the launcher.
 
So here is my next attempt

PEspring = Wgrav + KE
(1/2)kx^2 = mgsin(theta)x + (1/2)mv^2

Is this correct?
 
Last edited:
Riman643 said:
So here is my next attempt

PEspring = Wgrav + KE
(1/2)kx^2 = mgsin(theta)x + (1/2)mv^2

Is this correct?
Looks right.
 
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