How Many Dynes to Change Length of Spring by 20cm?

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To change the length of a spring by 20 cm, it requires 400 dynes, calculated by multiplying the force needed for a 5 cm change by four. Springs operate linearly, allowing for direct proportionality in force and displacement. For a more formal approach, one can determine the spring constant (k) using the formula Fspring = k*x, where Fspring is the force and x is the displacement. The discussion confirms that the initial calculation is correct and no additional formulas are necessary. Understanding the linear nature of springs simplifies the calculation process.
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The question is... suppose it requires 100 dynes to change the length of a certain spring 5 cm. What force is required to change the length of the spring 20 cm?

Would you just multiply it... and say it would take 400 dynes?
 
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Sounds good to me :smile: Springs are linear. If you wanted to be more formal about it, you could find the spring constant k from Fspring=k*x since you know Fspring and you know x.
 
Okay, thank you! Just wanted to make sure i wasn't missing a formula somewhere
 
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