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

[tuffshorty]

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?

 

[Saladsamurai]

Sounds good to me Springs are linear. If you wanted to be more formal about it, you could find the spring constant k from F_spring=k*x since you know F_spring and you know x.

 

[tuffshorty]

Okay, thank you! Just wanted to make sure i wasn't missing a formula somewhere