Object Oscillation & Spring Shortening: Find the Answer!

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    Oscillation Spring
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Discussion Overview

The discussion revolves around the oscillation of a mass-spring system, specifically focusing on the effects of removing a mass from a spring and how it affects the spring's length. Participants explore the relationship between oscillation period, spring constant, and the resulting displacement of the spring when the mass is removed. The scope includes mathematical reasoning and conceptual clarification related to oscillatory motion and forces acting on the spring.

Discussion Character

  • Mathematical reasoning
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant presents a scenario involving a 6.2 kg object oscillating with a period of 0.3 seconds and a spring constant of 2755 N/m, asking how much the spring shortens when the object is removed.
  • Another participant suggests using the angular frequency formula \( w = \frac{2\pi}{t} \) to find the angular frequency and attempts to relate it to the spring's behavior.
  • A participant expresses confusion over not obtaining the expected answer of 0.022 m when using the formula for a pendulum, indicating a potential misunderstanding of the system being analyzed.
  • Another participant corrects the previous claim about the formula, stating that the correct formula for a mass on a spring is \( \omega = \sqrt{\frac{K}{m}} \) and emphasizes that the elastic force must equal the gravitational force when the mass is at rest.
  • There is a discussion about the forces acting on the spring, specifically the elastic force \( F_e = Ky \) and gravitational force \( F_G = mg \), leading to the conclusion that these forces balance when the mass is attached.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the correct approach to solve the problem, and there are competing views on the appropriate formulas and methods to use. The discussion remains unresolved regarding the specific calculations and the expected answer.

Contextual Notes

There are unresolved assumptions regarding the definitions of variables and the applicability of certain formulas to the mass-spring system versus a pendulum. The participants have not fully clarified the conditions under which their equations apply.

leprofece
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1 object of 6.2 Kg hangs 1 balance of spring mass and performs an oscillation of each 0.3 sec If K = 2755 n/m?
How much shortens the spring by removing the object?
Use pi ^ 2 as 10
 
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leprofece said:
1 object of 6.2 Kg hangs 1 balance of spring mass and performs an oscillation of each 0.3 sec If K = 2755 n/m?
How much shortens the spring by removing the object?
Use pi ^ 2 as 10

Can you add some thoughts please?
Perhaps some relevant equations?
 
I like Serena said:
Can you add some thoughts please?
Perhaps some relevant equations?

maybe w= 2pi/t
w= 6,28/0,3

I tried (2pi)sqrt(L/g) solve to L But I don't get the 0.022 m that is the book answer

it could be get the aceleration to get the force
to try f = Kx

SO CAN anybody help me?
 
Last edited:
leprofece said:
maybe w= 2pi/t
w= 6,28/0,3

I tried (2pi)sqrt(L/g) solve to L But I don't get the 0.022 m that is the book answer

I'm afraid that is the formula for a pendulum with length L.
The formula for a mass on a spring is
$$\omega = \sqrt{\frac K m}$$

For this problem we won't need it though.
It appears you have more information than you need.
it could be get the aceleration to get the force
to try f = Kx

Good!
Let's pick $y$ for the coordinate though, to emphasize it's a vertical coordinate.
So we have an elastic force $F_e$:
$$F_e = Ky$$
And we also have the force of gravity.
$$F_G = mg$$

When the mass is at rest, the elastic force and the force of gravity have to be equal and opposite.
That is:
$$F_e = F_G$$
$$Ky = mg$$

Now if we remove the mass from the spring, the spring will return to its neutral position at $y=0$.
What can you conclude then about the $y$ where the mass was at rest before?
 

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