If you see random sparks on top of a hot cooktop when you use a lighter, it's likely due to a phenomenon called "piezoelectric sparking." Piezoelectric sparking is a common mechanism used in many lighters, including gas stovetop lighters, to create a spark for ignition.
Here's how it works:
Piezoelectric crystal: Inside the lighter, there's a small piezoelectric crystal. When you press the button or trigger on the lighter, it compresses the crystal.
Creation of electric charge: The compression of the piezoelectric crystal generates an electric charge. This is a result of the crystal's unique property, known as the piezoelectric effect, which converts mechanical stress into electrical energy.
Release of electric charge: When the pressure is released, the piezoelectric crystal rapidly expands back to its original shape. This sudden release of stress causes the stored electrical energy to discharge as a high-voltage spark.
Spark ignition: The high-voltage spark jumps across a small gap and ignites the gas released from the lighter's nozzle. This is similar to how a spark plug works in an internal combustion engine.
Now, when you use a lighter near a hot cooktop, especially a gas or induction cooktop, you may observe sparks due to the following reasons:
Residual gas: There might be some residual gas or fumes around the cooktop's burner area, especially if you've recently used it. When the lighter's spark comes into contact with these gas fumes, it can ignite and create a visible spark.
Dust or debris: If the cooktop's surface or surrounding area is dusty or has accumulated debris, the spark from the lighter may cause small particles to ignite, leading to visible sparks.
It's essential to be cautious when using a lighter near a cooktop or any flammable materials. Always ensure proper ventilation in your kitchen and keep the cooktop clean to minimize the risk of accidental fires. If you frequently encounter sparks or suspect a problem with your lighter, consider getting it checked or replaced to ensure safe operation.