What is the largest mass that can be placed on the spring

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The discussion focuses on calculating the maximum mass that can be placed on a spring with a force constant of 1.50 N/m and a maximum extension of 10 cm. The initial calculations yield a mass of 0.0153 kg, but the textbook states the correct answer is 0.153 kg. Participants suggest using force analysis for static equilibrium instead of energy equations, as the force exerted by the spring varies with extension. A free body diagram is recommended to clarify the solution. Ultimately, accurate calculations and understanding of Hooke's Law are essential for determining the correct mass limit.
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Homework Statement


the spring in a typical hooke's law apparatus has a force constant of 1.50 N/m and a maximum extension of 10cm. what is the largest mass that can be placed on the spring without damaging it?


Homework Equations


what i believe to be relevant:
F=-kx
W=F"d
E=mg(h)


The Attempt at a Solution


F=1.5(0.10)
F=0.15

W=F"d
W=0.15(0.10)
W=0.015J

0.015=m(9.81)(0.10)
0.015/0.981=m
m=0.0153kg <----------- answer

now i have no idea how this can be wrong.. i have gone over it many times now.
my textbook has it as 0.153kg.
am i right on this one?
 
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jaron said:

Homework Statement


the spring in a typical hooke's law apparatus has a force constant of 1.50 N/m and a maximum extension of 10cm. what is the largest mass that can be placed on the spring without damaging it?


Homework Equations


what i believe to be relevant:
F=-kx
W=F"d
E=mg(h)


The Attempt at a Solution


F=1.5(0.10)
F=0.15

W=F"d
W=0.15(0.10)
W=0.015J

0.015=m(9.81)(0.10)
0.015/0.981=m
m=0.0153kg <----------- answer

now i have no idea how this can be wrong.. i have gone over it many times now.
my textbook has it as 0.153kg.
am i right on this one?

I was able to solve this by using a force analysis. You don't need to even use energy.

Try finding what mass puts the system in static equilibrium at the spring's maximum extension and solve for mass.

There might be a way to solve it with the energy equations, but I don't really see a need to go that route. The only thing I can see is if you go that direction, the force exerted by the spring isn't constant, it's a function of x. But like I said, you don't even need to go that route.

Draw a free body diagram and the answer should be obvious.
 
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