The lag you're experiencing is likely a combination of factors:
1. Third-party hosting issues - Many unblocked game sites host older versions or use slower servers. The physics engine can struggle when the game files aren't optimized or compressed properly.
2. Browser hardware acceleration - Definitely worth enabling. In Chrome/Edge go to Settings > System and turn on "Use hardware acceleration when available." This offloads graphics processing to your GPU instead of relying on CPU alone.
3. Cache and memory - Browser games don't clear cache well. Try clearing your browser cache (Ctrl+Shift+Delete) and cookies for that site specifically. Sometimes old corrupted data causes performance issues.
4. Background tabs - Close other tabs and extensions. Even on fast internet, if your browser RAM is maxed out, physics-heavy levels will stutter.
5. Browser choice - Chrome usually handles WebGL games best, but Firefox with hardware acceleration can also work well. Edge is hit or miss.
Try the hardware acceleration first - that usually fixes most physics-related lag. If that doesn't work, clearing cache is the next step.