From b9dde8e32eaed402ce250a52f144abea37f432c5 Mon Sep 17 00:00:00 2001
From: rgeorgi <russellgeorgi@gmail.com>
Date: Sat, 28 Aug 2021 12:57:29 -0700
Subject: [PATCH] 3-11

---
 3-11.html | 132 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 132 insertions(+)
 create mode 100644 3-11.html
diff --git a/3-11.html b/3-11.html
new file mode 100644
index 0000000..6ae31d7
--- /dev/null
+++ b/3-11.html
@@ -0,0 +1,132 @@
+<!--
+    This work is licensed under CC BY-NC-ND 4.0            
+    Link to license: http://creativecommons.org/licenses/by-nc-nd/4.0/
+    Attribute to Russell Georgi
+-->
+<html>
+    <head>
+        <title>
+            Problem 3-11
+        </title>
+        <style>
+            html, body {
+                width:  100%;
+                height: 100%;
+                margin: 0px;
+                border: 0;
+                overflow: hidden;
+                display: block;
+            }
+
+            canvas {
+                position: absolute;
+            }
+        </style>
+    </head>
+    <body>       
+        <canvas id="myCanvas" width="1" height="1" style="border:1px solid #ffffff;">
+        Your browser does not support the HTML5 canvas tag.</canvas>
+        
+        <script>
+        var c = document.getElementById("myCanvas");
+        var ctx = c.getContext("2d");
+        c.width = window.innerWidth;
+        c.height = window.innerHeight;
+        //Time step
+        var dt = 0.002;
+        var t = 0;
+        var g = 980;
+        var y = 10;
+        var yp = 0;
+        var l = 200;
+        var fallT = 0;
+        var a = Math.sqrt(g / l);
+        //Relative position of canvas
+        var xPos = 0;
+        var yPos = 200;
+        //Moves and scales canvas
+        ctx.translate(ctx.canvas.width / 2, ctx.canvas.height / 2)
+        ctx.scale(1, -1);
+
+        function Reset()
+        {
+            t = 0;
+            fallT = 0;
+            y = 10;
+        }
+        Reset();
+
+        function Clear(ctx)
+        {
+            ctx.clearRect(-c.width, -c.height, c.width * 2, c.height * 2);
+        }
+
+        function Update()
+        {
+            Clear(ctx);
+            Draw();
+            t += dt;
+            if (t > 2.5)
+            {
+                Reset();
+            }
+            if (y <= l)
+            {
+                y = 10 * Math.cosh(a * t);
+            } else
+            {
+                if (fallT == 0)
+                {
+                    fallT = t;
+                }
+                y += (a * Math.sqrt(l ** 2 + 100) + g * (t- fallT)) * dt;
+            }
+            setTimeout(Update, 1000/60);
+        }
+    
+        function Draw()
+        {
+            ctx.strokeStyle = "#ee0000";
+            ctx.lineWidth = 2;
+            if (y <= l)
+            {
+                ctx.beginPath();
+                ctx.moveTo(xPos, yPos);
+                ctx.lineTo(xPos, yPos - y);
+                ctx.stroke();
+                ctx.beginPath();
+                ctx.moveTo(xPos, yPos);
+                ctx.lineTo(xPos + (l - y), yPos);
+                ctx.stroke();
+            } else
+            {
+                ctx.beginPath();
+                ctx.moveTo(xPos, yPos - y);
+                ctx.lineTo(xPos, yPos - y + l);
+                ctx.stroke();
+            }
+            ctx.lineWidth = 1;
+            ctx.strokeStyle = "#000000";
+            ctx.beginPath();
+            ctx.moveTo(xPos + 2, -c.height);
+            ctx.lineTo(xPos + 2, yPos - 2);
+            ctx.lineTo(c.width, yPos - 2);
+            ctx.stroke();
+        }
+
+
+        window.addEventListener('resize', function(event) {
+            c.width = window.innerWidth;
+            c.height = window.innerHeight;
+            ctx.translate(c.width / 2, c.height / 2);
+            ctx.scale(1, -1);
+        }, true);
+
+        Update();
+
+        </script>
+    </body>
+    <p xmlns:cc="http://creativecommons.org/ns#" style="font-size: 1vw; bottom: 0px; position: absolute;">
+        This work is licensed under 
+        <a href="http://creativecommons.org/licenses/by-nc-nd/4.0/?ref=chooser-v1" target="_blank" rel="license noopener noreferrer" style="display:inline-block;">CC BY-NC-ND 4.0<img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/cc.svg?ref=chooser-v1"><img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/by.svg?ref=chooser-v1"><img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/nc.svg?ref=chooser-v1"><img style="height:22px!important;margin-left:3px;vertical-align:text-bottom;" src="https://mirrors.creativecommons.org/presskit/icons/nd.svg?ref=chooser-v1"></a></p>
+</html>
\ No newline at end of file
