Simple Mass Spring System Homework: Finding Distance, Work, and Power

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The discussion revolves around a mass-spring system where a 7 kg block compresses a spring with a constant of 27 N/m by 0.15 m. Key calculations involve determining how far the block slides before stopping, the work done by the spring, and the work done by friction, which has a coefficient of 0.55. Participants suggest using conservation of energy principles to find the initial velocity of the block as it is launched by the spring. The conversation emphasizes the importance of understanding the forces at play, including spring force and frictional force. The thread highlights the need for clear calculations to solve the homework problems effectively.
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Homework Statement



consider a mass spring system mounted on a horizontal surface. The left end of the spring is rigidly mounted, and the spring constant is 27 N/m. A block with a mass of 7 kg is placed on the right side of the spring and compresses the spring a distance of .15 m. The region on the horizontal surface under the spring from the barrier on the left side to the equilibrium length of the spring is frictionless. The region of the horizontal surface to the right of the equilibrium length of the spring has a coefficient of kinetic friction equal to .55.
A. How far does the block slide before it stops?
B. How much work is done on the block by the spring? How much work is done on the block by friction?
C. What is the power dissipated by friction?

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The Attempt at a Solution

 
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I'm thrown off because I don't have the velocity of the block as it starts from rest and is launched by the spring. Do I use conservation of energy?
 
Harshmau5 said:
Do I use conservation of energy?
That's a good start.
 
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