I am trying to simulate a spring in a time-stepped manner. Mostly to sus out the correct order of operations, where to apply delta time, how to apply drag.

As such I have set up, with the new Desmos functions features, a time generator that randomly applies latency at each step and a velocity and y position generator. I have plugged in hookes law into the velocity update method.

Initially I set the y position to 1 and give it 0 velocity. There is not supposed to be gravity or anything in this simulation. Only the spring and eventually drag. It is suppose to oscillate around and eventually settle on 0.

I update velocity with V = -40 * y ^2 * sign(y) * dt each step.

This is the graph I get. The problem is every time I set up my constants the result is a simulation that grows in energy. Rather than settling on 0 it oscillates further and further away from 0. I am not sure why. Am I missing something about hookes law or how I am applying it?

I maybe wouldn't be surprised if it oscillated to the same point every time... but growing each time?? Thats a surprise.

Here is the graph

https://preview.redd.it/u4vptv9ozbsa1.png?width=1416&format=png&auto=webp&s=198be62f4c1b22561f6d021a2d168ac0d4127810