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Aggie
Mar13-07, 12:27 AM
A block of mass 0.08 kg is pushed against a spring with spring constant k=31 N/m. The srping is compressed 0.15 meters from its natural length. The block is released and it slides along a surface with coefficient of frition 0.45. How far does the block travel from the point at which is is released?


I am having a problem developing an equation for this. It seems i am always short on something.

this is what i have so far

Work due to friction - work due to spring = work due to spring - work due to friction.

I know i am missing something but i don't know what it is.

denverdoc
Mar13-07, 01:10 AM
Assume it is all horizontal. You have an initial set of numbers to calculate the force along the x axis and the frictional forces, Soecifty these, and we can help more.

Aggie
Mar13-07, 04:01 AM
is my equation right or wrong

Mentz114
Mar13-07, 12:14 PM
Your equation says

1 = -1

Forget the spring and think about what happens if you just push the block with force f for 1 cm. Then return to the spring ...