Using Energy and Impulse to Solve a Mass on a Spring Problem

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The discussion revolves around a mass hanging from a spring that is struck by an impulse, leading to questions about how high it rises above the equilibrium position. The forces acting on the mass include gravity, the restoring force, and the applied impulse. It is noted that the restoring force cancels out the weight of the mass, leaving only the applied force to consider. The conversation emphasizes using energy principles rather than solely relying on Newton's Laws to determine the final distance from equilibrium. Ultimately, understanding how to apply impulse to calculate initial energy is crucial for solving the problem effectively.
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A mass m hangs from a spring. The natural angular frequency of the system is given in radians per second. The mass, while hanging at rest in equilibrium is struck from below and an impulse of x Newtons is imparted on the mass. How high above the equilibrium position does the mass rise?

So at the point in time where the mass is struck, the forces acting on it are gravity, the restoring force and the applied force. The restoring force (ks) is acting upwards and cancels with the weight (-mg), right? So we are left with the applied force. But how do use the impulse and angular frequency to progress from here?
 
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Think about the energy.
 
You're thinking in the correct direction in terms of Newton's Laws, but there is a much easier way to approach this using energy (as voko said).
Energy will give you the final distance from equilibrium, but you just need to figure out how to use impulse to solve for your initial energy.
 
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