<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Catapult Field Effect</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      user-select: none;
      -webkit-user-select: none;
    }

    body {
      width: 100%;
      background: #ffffff;
      color: #1e293b;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: flex-start;
      padding: 8px 8px 12px;
    }

    .controls {
      display: flex;
      gap: 8px;
      margin-bottom: 8px;
      flex-wrap: wrap;
      justify-content: center;
    }

    .btn {
      padding: 6px 14px;
      border-radius: 20px;
      border: 1.5px solid #cbd5e1;
      background: #f8fafc;
      color: #475569;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
    }

    .btn:hover {
      background: #e2e8f0;
      color: #1e293b;
    }

    .btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
    }

    .svg-container {
      width: 100%;
      max-width: 520px;
      position: relative;
    }

    svg {
      width: 100%;
      height: auto;
      display: block;
    }

    /* Animated rubber-band pulse */
    .field-band {
      stroke-dasharray: 8 6;
      animation: fieldFlow 2.5s linear infinite;
    }

    @keyframes fieldFlow {
      to {
        stroke-dashoffset: -28;
      }
    }

    .force-pulse {
      animation: pulseArrow 1.8s ease-in-out infinite alternate;
      transform-origin: 250px 225px;
    }

    @keyframes pulseArrow {
      0% {
        transform: translateY(0);
        opacity: 0.9;
      }
      100% {
        transform: translateY(5px);
        opacity: 1;
      }
    }

    .hidden {
      display: none;
    }
  </style>
</head>
<body>

  
  <div class="controls">
    <button id="btnCatapult" class="btn active" onclick="setMode('catapult')">Catapult Field</button>
    <button id="btnSeparated" class="btn" onclick="setMode('separated')">Separate Fields</button>
  </div>

  <div class="svg-container">
    <svg viewBox="0 0 500 315" aria-label="Catapult field magnetic force diagram">
      <defs>
        
        <marker id="arr-mag" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="6" markerHeight="6" orient="auto">
          <path d="M 0 1 L 8 5 L 0 9 z" fill="#0284c7" />
        </marker>
        <marker id="arr-force" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="7" markerHeight="7" orient="auto">
          <path d="M 0 1 L 8 5 L 0 9 z" fill="#16a34a" />
        </marker>
        <marker id="arr-circ" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="6" markerHeight="6" orient="auto">
          <path d="M 0 1 L 8 5 L 0 9 z" fill="#d97706" />
        </marker>

        
        <filter id="shadow" x="-10%" y="-10%" width="120%" height="120%">
          <feDropShadow dx="0" dy="2" stdDeviation="3" flood-opacity="0.15" />
        </filter>
      </defs>

      
      
      <g filter="url(#shadow)">
        <rect x="15" y="75" width="75" height="190" rx="8" fill="#ef4444" />
        <rect x="72" y="75" width="18" height="190" rx="0" fill="#dc2626" opacity="0.35" />
        <text x="52" y="180" fill="#ffffff" font-size="34" font-weight="800" text-anchor="middle" dominant-baseline="central">N</text>
      </g>

      
      <g filter="url(#shadow)">
        <rect x="410" y="75" width="75" height="190" rx="8" fill="#3b82f6" />
        <rect x="410" y="75" width="18" height="190" rx="0" fill="#1d4ed8" opacity="0.35" />
        <text x="448" y="180" fill="#ffffff" font-size="34" font-weight="800" text-anchor="middle" dominant-baseline="central">S</text>
      </g>

      
      <g id="catapultLayer">
        
        <path class="field-band" d="M 90 95 C 180 38, 320 38, 410 95" fill="none" stroke="#0284c7" stroke-width="3" />
        <path class="field-band" d="M 90 120 C 185 68, 315 68, 410 120" fill="none" stroke="#0284c7" stroke-width="3" />
        <path class="field-band" d="M 90 145 C 190 98, 310 98, 410 145" fill="none" stroke="#0284c7" stroke-width="3" />
        <path class="field-band" d="M 90 170 C 195 128, 305 128, 410 170" fill="none" stroke="#0284c7" stroke-width="3" />

        
        <path d="M 90 220 C 195 255, 305 255, 410 220" fill="none" stroke="#93c5fd" stroke-width="2" stroke-dasharray="6 6" />
        <path d="M 90 245 C 200 275, 300 275, 410 245" fill="none" stroke="#bfdbfe" stroke-width="1.8" stroke-dasharray="6 6" />

        
        
        <g>
          <rect x="155" y="8" width="190" height="22" rx="11" fill="#f0f9ff" stroke="#0284c7" stroke-width="1.2" />
          <text x="250" y="19" fill="#0369a1" font-size="11.5" font-weight="700" text-anchor="middle" dominant-baseline="central">Stronger Field (Reinforced)</text>
        </g>

        
        <g>
          <rect x="160" y="282" width="180" height="22" rx="11" fill="#f8fafc" stroke="#94a3b8" stroke-width="1.2" />
          <text x="250" y="293" fill="#64748b" font-size="11.5" font-weight="600" text-anchor="middle" dominant-baseline="central">Weaker Field (Cancelled)</text>
        </g>

        
        <g class="force-pulse">
          <line x1="250" y1="198" x2="250" y2="258" stroke="#16a34a" stroke-width="5.5" stroke-linecap="round" marker-end="url(#arr-force)" />
          <rect x="180" y="222" width="140" height="22" rx="11" fill="#f0fdf4" stroke="#86efac" stroke-width="1.2" />
          <text x="250" y="233" fill="#15803d" font-size="11.5" font-weight="800" text-anchor="middle" dominant-baseline="central">Force (F) ↓</text>
        </g>
      </g>

      
      <g id="separatedLayer" class="hidden">
        
        <line x1="90" y1="105" x2="400" y2="105" stroke="#0284c7" stroke-width="2.2" marker-end="url(#arr-mag)" />
        <line x1="90" y1="140" x2="400" y2="140" stroke="#0284c7" stroke-width="2.2" marker-end="url(#arr-mag)" />
        <line x1="90" y1="200" x2="400" y2="200" stroke="#0284c7" stroke-width="2.2" marker-end="url(#arr-mag)" />
        <line x1="90" y1="235" x2="400" y2="235" stroke="#0284c7" stroke-width="2.2" marker-end="url(#arr-mag)" />

        
        <circle cx="250" cy="170" r="42" fill="none" stroke="#d97706" stroke-width="2.2" stroke-dasharray="6 4" />
        <circle cx="250" cy="170" r="68" fill="none" stroke="#d97706" stroke-width="1.8" stroke-dasharray="6 4" />

        
        <path d="M 250 102 L 242 102" stroke="#d97706" stroke-width="2.2" marker-end="url(#arr-circ)" />
        <path d="M 250 238 L 258 238" stroke="#d97706" stroke-width="2.2" marker-end="url(#arr-circ)" />

        
        <g>
          <rect x="165" y="8" width="170" height="22" rx="11" fill="#f0f9ff" stroke="#0284c7" stroke-width="1.2" />
          <text x="250" y="19" fill="#0284c7" font-size="11.5" font-weight="700" text-anchor="middle" dominant-baseline="central">Uniform Field (N → S)</text>
        </g>
        <g>
          <rect x="145" y="282" width="210" height="22" rx="11" fill="#fffbeb" stroke="#f59e0b" stroke-width="1.2" />
          <text x="250" y="293" fill="#b45309" font-size="11.5" font-weight="700" text-anchor="middle" dominant-baseline="central">Wire Field (Counter-Clockwise)</text>
        </g>
      </g>

      
      <g id="wire" filter="url(#shadow)">
        <circle cx="250" cy="170" r="20" fill="#ffedd5" stroke="#ea580c" stroke-width="3" />
        
        <circle cx="250" cy="170" r="5.5" fill="#c2410c" />
        
        
        <rect x="195" y="137" width="110" height="20" rx="10" fill="#fff7ed" stroke="#f97316" stroke-width="1" />
        <text x="250" y="147" fill="#9a3412" font-size="11" font-weight="700" text-anchor="middle" dominant-baseline="central">Current ⊙ (Out)</text>
      </g>
    </svg>
  </div>

  <script>
    function setMode(mode) {
      const catapultLayer = document.getElementById('catapultLayer');
      const separatedLayer = document.getElementById('separatedLayer');
      const btnCatapult = document.getElementById('btnCatapult');
      const btnSeparated = document.getElementById('btnSeparated');

      if (mode === 'catapult') {
        catapultLayer.classList.remove('hidden');
        separatedLayer.classList.add('hidden');
        btnCatapult.classList.add('active');
        btnSeparated.classList.remove('active');
      } else {
        catapultLayer.classList.add('hidden');
        separatedLayer.classList.remove('hidden');
        btnCatapult.classList.remove('active');
        btnSeparated.classList.add('active');
      }
    }
  </script>
</body>
</html>

Force on a Current-Carrying Conductor

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      width: 100%;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      background: transparent;
      color: #1e2945;
      padding: 8px;
    }
    .grid {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      justify-content: center;
      width: 100%;
    }
    .panel {
      flex: 1 1 240px;
      max-width: 330px;
      min-width: 200px;
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 12px;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    }
    .panel-title {
      font-size: 15px;
      font-weight: 700;
      margin-bottom: 8px;
      color: #334155;
    }
    .svg-wrap {
      width: 100%;
      height: 180px;
    }
    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }
    .badge {
      margin-top: 10px;
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 700;
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }
    .badge-success {
      background: #dcfce7;
      color: #15803d;
      border: 1px solid #86efac;
    }
    .badge-none {
      background: #fee2e2;
      color: #b91c1c;
      border: 1px solid #fca5a5;
    }
    .magnet-n { fill: #ef4444; }
    .magnet-s { fill: #3b82f6; }
    .pole-text {
      fill: #ffffff;
      font-size: 14px;
      font-weight: 800;
      text-anchor: middle;
      dominant-baseline: central;
    }
    .field-line {
      stroke: #94a3b8;
      stroke-width: 2;
      stroke-dasharray: 4 3;
    }
    .wire {
      stroke: #d97706;
      stroke-width: 7;
      stroke-linecap: round;
    }
    .angle-arc {
      fill: none;
      stroke: #64748b;
      stroke-width: 1.5;
    }
    .label-text {
      font-size: 11px;
      font-weight: 600;
      fill: #475569;
    }
  </style>
</head>
<body>

  <div class="grid">
    
    <div class="panel">
      <div class="panel-title">Perpendicular (90°)</div>
      <div class="svg-wrap">
        <svg viewBox="0 0 260 170">
          <defs>
            <marker id="arrow-field" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="6" markerHeight="6" orient="auto">
              <path d="M 0 1 L 8 5 L 0 9 z" fill="#94a3b8" />
            </marker>
            <marker id="arrow-force" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="7" markerHeight="7" orient="auto">
              <path d="M 0 1 L 8 5 L 0 9 z" fill="#16a34a" />
            </marker>
            <marker id="arrow-current" viewBox="0 0 10 10" refX="6" refY="5" markerWidth="6" markerHeight="6" orient="auto">
              <path d="M 0 1 L 8 5 L 0 9 z" fill="#b45309" />
            </marker>
          </defs>

          
          <rect x="15" y="30" width="30" height="110" rx="4" class="magnet-n" />
          <text x="30" y="85" class="pole-text">N</text>

          <rect x="215" y="30" width="30" height="110" rx="4" class="magnet-s" />
          <text x="230" y="85" class="pole-text">S</text>

          
          <line x1="48" y1="55" x2="210" y2="55" class="field-line" marker-end="url(#arrow-field)" />
          <line x1="48" y1="85" x2="210" y2="85" class="field-line" marker-end="url(#arrow-field)" />
          <line x1="48" y1="115" x2="210" y2="115" class="field-line" marker-end="url(#arrow-field)" />

          
          <path d="M 130 73 L 140 73 L 140 85" fill="none" stroke="#64748b" stroke-width="1.5" />

          
          <line x1="130" y1="20" x2="130" y2="150" class="wire" />
          <line x1="130" y1="135" x2="130" y2="40" stroke="#fef08a" stroke-width="3" marker-end="url(#arrow-current)" />
          <text x="114" y="32" class="label-text" font-weight="700" fill="#b45309">I</text>

          
          <line x1="130" y1="85" x2="185" y2="35" stroke="#16a34a" stroke-width="4" marker-end="url(#arrow-force)" />
          <text x="185" y="28" font-size="14" font-weight="800" fill="#16a34a">F</text>
        </svg>
      </div>
      <div class="badge badge-success">Max Force (F = max)</div>
    </div>

    
    <div class="panel">
      <div class="panel-title">Parallel (0°)</div>
      <div class="svg-wrap">
        <svg viewBox="0 0 260 170">
          
          <rect x="15" y="30" width="30" height="110" rx="4" class="magnet-n" />
          <text x="30" y="85" class="pole-text">N</text>

          <rect x="215" y="30" width="30" height="110" rx="4" class="magnet-s" />
          <text x="230" y="85" class="pole-text">S</text>

          
          <line x1="48" y1="55" x2="210" y2="55" class="field-line" marker-end="url(#arrow-field)" />
          <line x1="48" y1="115" x2="210" y2="115" class="field-line" marker-end="url(#arrow-field)" />

          
          <line x1="50" y1="85" x2="208" y2="85" class="wire" />
          <line x1="60" y1="85" x2="190" y2="85" stroke="#fef08a" stroke-width="3" marker-end="url(#arrow-current)" />
          <text x="126" y="75" class="label-text" font-weight="700" fill="#b45309">I</text>

          
          <circle cx="130" cy="138" r="14" fill="#fee2e2" stroke="#dc2626" stroke-width="1.5" />
          <text x="130" y="142" font-size="13" font-weight="800" fill="#dc2626" text-anchor="middle">F</text>
          <line x1="120" y1="148" x2="140" y2="128" stroke="#dc2626" stroke-width="2.5" />
        </svg>
      </div>
      <div class="badge badge-none">No Force (F = 0)</div>
    </div>
  </div>

</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Magnetic Fields Comparison</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #f8f9fa;
      color: #1e2945;
      width: 100%;
      min-height: 100%;
      display: flex;
      justify-content: center;
      align-items: center;
      padding: 12px;
    }

    .diagram-container {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 24px;
      width: 100%;
      max-width: 680px;
    }

    .panel {
      display: flex;
      flex-direction: column;
      align-items: center;
      width: 100%;
    }

    .panel-title {
      font-size: 15px;
      font-weight: 700;
      color: #1e2945;
      margin-bottom: 8px;
      text-align: center;
    }

    .svg-canvas {
      width: 100%;
      height: auto;
      max-height: 220px;
      display: block;
    }

    /* Slow, steady flow animations */
    .flow-line-circular {
      stroke-dasharray: 8, 8;
      animation: rotateFlow 14s linear infinite;
    }

    .flow-line-straight {
      stroke-dasharray: 8, 8;
      animation: forwardFlow 8s linear infinite;
    }

    @keyframes forwardFlow {
      from { stroke-dashoffset: 32; }
      to { stroke-dashoffset: 0; }
    }

    @keyframes rotateFlow {
      from { stroke-dashoffset: 64; }
      to { stroke-dashoffset: 0; }
    }

    @media (prefers-reduced-motion: reduce) {
      .flow-line-circular, .flow-line-straight {
        animation: none;
        stroke-dasharray: none;
      }
    }
  </style>
</head>
<body>

  <div class="diagram-container">
    
    <div class="panel">
      <h2 class="panel-title">Field Around a Wire</h2>
      <svg class="svg-canvas" viewBox="0 0 240 200" aria-label="Circular magnetic field around a current-carrying wire">
        <defs>
          <marker id="arrow-blue" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="6" markerHeight="6" orient="auto-start-reverse">
            <path d="M 0 1.5 L 8 5 L 0 8.5 z" fill="#0284c7" />
          </marker>
        </defs>

        
        
        <circle cx="120" cy="88" r="72" fill="none" stroke="#0284c7" stroke-width="2" class="flow-line-circular" opacity="0.85" />
        
        <circle cx="120" cy="88" r="50" fill="none" stroke="#0284c7" stroke-width="2" class="flow-line-circular" opacity="0.9" />
        
        <circle cx="120" cy="88" r="30" fill="none" stroke="#0284c7" stroke-width="2" class="flow-line-circular" />

        
        
        <path d="M 124 16 L 116 16" fill="none" stroke="#0284c7" stroke-width="2.5" marker-end="url(#arrow-blue)" />
        <path d="M 124 38 L 116 38" fill="none" stroke="#0284c7" stroke-width="2.5" marker-end="url(#arrow-blue)" />
        
        <path d="M 116 160 L 124 160" fill="none" stroke="#0284c7" stroke-width="2.5" marker-end="url(#arrow-blue)" />
        <path d="M 116 138 L 124 138" fill="none" stroke="#0284c7" stroke-width="2.5" marker-end="url(#arrow-blue)" />
        
        <path d="M 48 84 L 48 92" fill="none" stroke="#0284c7" stroke-width="2.5" marker-end="url(#arrow-blue)" />
        
        <path d="M 192 92 L 192 84" fill="none" stroke="#0284c7" stroke-width="2.5" marker-end="url(#arrow-blue)" />

        
        <circle cx="120" cy="88" r="14" fill="#fde68a" stroke="#d97706" stroke-width="2.5" />
        
        <circle cx="120" cy="88" r="4.5" fill="#1e2945" />

        
        <rect x="75" y="172" width="90" height="22" rx="6" fill="#f8f9fa" />
        <text x="120" y="187" text-anchor="middle" font-size="11" font-weight="700" fill="#1e2945">Current (out ⊙)</text>
      </svg>
    </div>

    
    <div class="panel">
      <h2 class="panel-title">External Magnetic Field</h2>
      <svg class="svg-canvas" viewBox="0 0 240 200" aria-label="Straight magnetic field lines flowing from North to South pole">
        <defs>
          <marker id="arrow-green" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="6" markerHeight="6" orient="auto-start-reverse">
            <path d="M 0 1.5 L 8 5 L 0 8.5 z" fill="#16a34a" />
          </marker>
        </defs>

        
        <g stroke="#16a34a" stroke-width="2" class="flow-line-straight">
          <line x1="48" y1="36" x2="192" y2="36" />
          <line x1="48" y1="64" x2="192" y2="64" />
          <line x1="48" y1="92" x2="192" y2="92" />
          <line x1="48" y1="120" x2="192" y2="120" />
          <line x1="48" y1="148" x2="192" y2="148" />
        </g>

        
        <path d="M 115 36 L 125 36" fill="none" stroke="#16a34a" stroke-width="2.5" marker-end="url(#arrow-green)" />
        <path d="M 115 64 L 125 64" fill="none" stroke="#16a34a" stroke-width="2.5" marker-end="url(#arrow-green)" />
        <path d="M 115 92 L 125 92" fill="none" stroke="#16a34a" stroke-width="2.5" marker-end="url(#arrow-green)" />
        <path d="M 115 120 L 125 120" fill="none" stroke="#16a34a" stroke-width="2.5" marker-end="url(#arrow-green)" />
        <path d="M 115 148 L 125 148" fill="none" stroke="#16a34a" stroke-width="2.5" marker-end="url(#arrow-green)" />

        
        <rect x="8" y="24" width="40" height="136" rx="4" fill="#ef4444" stroke="#dc2626" stroke-width="2" />
        <text x="28" y="99" text-anchor="middle" font-size="22" font-weight="800" fill="#ffffff">N</text>

        
        <rect x="192" y="24" width="40" height="136" rx="4" fill="#3b82f6" stroke="#2563eb" stroke-width="2" />
        <text x="212" y="99" text-anchor="middle" font-size="22" font-weight="800" fill="#ffffff">S</text>

        
        <text x="120" y="187" text-anchor="middle" font-size="11" font-weight="700" fill="#1e2945">N → S Field Lines</text>
      </svg>
    </div>
  </div>

</body>
</html>

UK-GCSE-SCIENCE-PHYS-MAG-02-03

Aligned learning resources

Related diagrams