How Does Wave Diffraction Work?

Wave diffraction is when waves bend around corners or through holes, just like water spreading out after a rock is removed from a pond.

Imagine you're playing with a toy boat in a puddle. If the puddle has a small opening, like a gate between two ponds, your boat can still move from one side to the other, even if it doesn't go straight through the gate. The water waves spread out on both sides of the gate, and that’s diffraction.

Diffraction happens because waves are flexible. When a wave hits an edge or goes through a small opening, it can’t stay in one line, it bends. This is like how a curtain flaps in the wind: when you pull back a part of it, the whole thing moves.

If the hole is big, the wave just continues straight on, like a river flowing into another. But if the hole is small, the wave spreads out in all directions, like water spilling from a bucket with a tiny tap.

You can see diffraction in real life too! When you hear someone talking around a corner, their voice bends around to reach your ears, that’s sound waves doing diffraction. It's the same reason radio signals can go through windows or doors, they spread out and find their way to you.