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+++ b/.gitignore
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+.jupyter_ystore.db
+.ipynb_checkpoints/
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diff --git a/Spring-Dimensioning.ipynb b/Spring-Dimensioning.ipynb
new file mode 100644
index 0000000..0793aa7
--- /dev/null
+++ b/Spring-Dimensioning.ipynb
@@ -0,0 +1,68 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": 17,
+   "id": "5bef2913-4855-471d-9594-5ec45c029048",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Length: 236.9 mm\n",
+      "Freq:   1.411 Hz\n"
+     ]
+    }
+   ],
+   "source": [
+    "import math\n",
+    "\n",
+    "# Parameters\n",
+    "spring_constant_n_mm = 1.1\n",
+    "spring_length_resting_mm = 112\n",
+    "\n",
+    "def spring_length_at(weight):\n",
+    "    return weight * 9.81 / spring_constant_n_mm + spring_length_resting_mm\n",
+    "\n",
+    "def resonant_freq_at(weight):\n",
+    "    return 1 / (2 * math.pi) * math.sqrt(spring_constant_n_mm * 1000 / weight)\n",
+    "\n",
+    "# Environment\n",
+    "weight_total_kg = 14\n",
+    "\n",
+    "print(f\"Length: {spring_length_at(weight_total_kg):.1f} mm\")\n",
+    "print(f\"Freq:   {resonant_freq_at(weight_total_kg):.3f} Hz\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "f21d84d9-c7a1-4fd2-aa32-136f04db32e5",
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.13.3"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}