Why does the period increase when the string length is increased?

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Discussion Overview

The discussion revolves around the relationship between the length of a string and the period of oscillation in a spring-like system. Participants explore the underlying reasons for the observed increase in period with increased string length, drawing parallels to pendulum behavior.

Discussion Character

  • Exploratory
  • Mathematical reasoning

Main Points Raised

  • One participant notes that the period is proportional to the square root of the string length and seeks to understand why increasing the length results in a longer period.
  • Another participant suggests that increasing the string length increases the distance that needs to be traveled, implying that it takes longer to complete one cycle if the speed remains unchanged.
  • A different participant emphasizes the need to clarify whether the speed or force remains constant to understand the relationship, and provides a mathematical derivation relating period to string length.
  • Responses include encouragement and suggestions to work through the problem on paper for better understanding.

Areas of Agreement / Disagreement

Participants express varying levels of understanding and provide different explanations, but there is no consensus on the underlying reasons for the relationship between string length and period. The discussion remains exploratory without a definitive resolution.

Contextual Notes

Some assumptions about constant speed and force are made, but these are not explicitly confirmed or explored in depth. The mathematical derivation presented relies on specific conditions that may not be universally applicable.

dumb
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hey,

i have to do an experiment about length of spring and its period, found the relationship, the period is proportional to the square root of the string length. (looks like a pendelum) but i don't understant why when u increase the length, the period increases! tell me y please! urgent :confused:
 
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By increasing the length of the string, you increase the distance the needed to travel. So even though you have not changed the amplitude or the mass at the end of the string it will still take longer to travel that distance. Simply, it takes longer to complete one cycle if it has further to travel if the speed is not changed.
 
You have to know if the speed stays the same, the force stays same or neither in order to see the relation. But since you say mention squareroot, i'll presume the force is the same.

acceleration 1= acceleration 2
acceleration=v^2/r
v=2*PI*r/T

So
acceleration=(2*PI*r/T)^2/r
=4*PI^2*r^2/T^2r
=4*Pi^2*r/T^2

So

T^2=4*Pi^2*r/a
T=2*PI*r^0.5/a^0.5

So this is the relation with the square root of the radius.
 
Nice mathematical explanation! :smile: Dumb, does that help you?
 
Dumb, if you do it on paper you'll understand better.
 
THANK U SOO MUCH EVERYONE :biggrin: :biggrin: , i did understand!
 

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