- #1
Spring Mechanics homework problem
- Thread starter aviv87
- Start date
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Homework Help Overview
The problem involves N weights, each of mass M, connected by springs, and asks for the acceleration of the top and bottom weights at the moment the top spring is cut. The context is spring mechanics and dynamics.
Discussion Character
- Exploratory, Assumption checking, Conceptual clarification
Approaches and Questions Raised
- Participants discuss the expected accelerations of the weights, with some guessing values based on gravitational acceleration and the effects of the springs. There are questions about the forces acting on each mass and the implications of the springs not changing lengths instantly.
Discussion Status
The discussion is ongoing, with participants sharing their thoughts and interpretations of the problem. Some guidance has been offered regarding the need to consider forces acting on the masses, and there is an exploration of differing opinions on the acceleration of the weights.
Contextual Notes
There is a lack of clarity regarding the arrangement of the weights and springs, as well as differing opinions on the accelerations involved, which may stem from assumptions about the system's behavior when the top spring is cut.
- #2
aviv87
- 17
- 0
anyone?
my guess is that the one on the top will have a=ng and the one on the bottom a=0.
is that right?
my guess is that the one on the top will have a=ng and the one on the bottom a=0.
is that right?
- #3
Doc Al
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- 45,584
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Since your attachment is not yet viewable, you'll have to describe the arrangement to get any help. What work have you done?
- #4
aviv87
- 17
- 0
there's a spring connected to a ceiling. a mass M is connected to it, to her another spring is connected, another mass etc' for N masses.
ceiling
-----
/
\
/
M
\
/
\
M
\
/
\
M
Does this help?
ceiling
-----
/
\
/
M
\
/
\
M
\
/
\
M
Does this help?
- #5
Doc Al
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Sounds right to me. But no need to guess. Consider the forces on each mass, and the fact that the springs won't change lengths instantly.aviv87 said:
- #6
aviv87
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- 0
Doc Al said:
Well, that's what I got, but my physics teacher said he thinks it's a=0 for the bottom one, but that the one on top would have a<g, but he wasn't sure.
That made me think I did something wrong...
- #7
Doc Al
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I don't see how he could think that the one on top could have an acceleration less than g. If the only force on it were gravity, a = g. But you've also got a stretched spring pulling it down, so a > g. Ask him to explain his reasoning.aviv87 said:
- #8
aviv87
- 17
- 0
Doc Al said:I don't see how he could think that the one on top could have an acceleration less than g. If the only force on it were gravity, a = g. But you've also got a stretched spring pulling it down, so a > g. Ask him to explain his reasoning.
My thoughts exactly
Well, I guess he wasn't paying enough attention or something...
Thanks!