Finding spring constant from a graph

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The discussion centers on determining the spring constant (k) from force/time and position/time graphs of an oscillating spring-mass system. It suggests using the relationship mgh = 1/2kx^2, but emphasizes that measuring the frequency of oscillation provides a more straightforward method to calculate k using the formula f = (1/2π)√(k/m). The clarity of the experiment setup is questioned, particularly whether the graphs were provided or measured. A free body diagram and force balance are recommended for further analysis. The conversation highlights the importance of experimental context in calculating the spring constant.
John Sena
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Assume a spring with a mass attached is oscillating.
Can i find spring constant from force/time and position/time graph using mgh=1/2kx^2?
The force in force/time graph is collected from force meter attached at the top of the spring.
The positin in position/time graph is the distance of the mass from the ground.
 
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John Sena said:
Assume a spring with a mass attached is oscillating.
Can i find spring constant from force/time and position/time graph using mgh=1/2kx^2?
The force in force/time graph is collected from force meter attached at the top of the spring.
The positin in position/time graph is the distance of the mass from the ground.

If you write a function for x(t) what do you get? x(t) = x(t=0) + ... Does this expression have k anywhere? How does this relate to an important time interval?
 
Draw a free body diagram for the mass, and write a force balance for the mass. What do you get?

Chet
 
John Sena said:
Assume a spring with a mass attached is oscillating.
Can i find spring constant from force/time and position/time graph using mgh=1/2kx^2?
The force in force/time graph is collected from force meter attached at the top of the spring.
The positin in position/time graph is the distance of the mass from the ground.

There is something not quite clear here and it requires a bit more explanation.

First of all, is this something that is part of a measurement or experiment? Are you simply given a spring with a mass, and it is ALREADY oscillating? How accurate do you need this to be?

You see, if this is simply an experiment or an observation, you can easily calculate the spring constant by simply measuring the frequency of oscillation. Measure how many times the mass makes a complete oscillation in one second, and you have the frequency of oscillation. Then simply use the fact that for a SHO system,

f = (1/2pi)*(sqr(k/m)

Knowing the mass, you immediately get the value of k.

Asking if you can find the spring constant from the force-time or position-time graph is vague. Were you GIVEN these or were you asked to measure these?

Zz.
 
For simple comparison, I think the same thought process can be followed as a block slides down a hill, - for block down hill, simple starting PE of mgh to final max KE 0.5mv^2 - comparing PE1 to max KE2 would result in finding the work friction did through the process. efficiency is just 100*KE2/PE1. If a mousetrap car travels along a flat surface, a starting PE of 0.5 k th^2 can be measured and maximum velocity of the car can also be measured. If energy efficiency is defined by...

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