Science Buddies: "Ask an Expert"

Hi! I'm trying to build the static electricity detector in this project https://www.sciencebuddies.org/science- ... #procedure and I have built it correctly (I have checked this many times and rebuilt it as well). Everything seems to be wired correctly because when I connect the battery the LED turns on. The problem is the LED won't react to anything. I have tried multiple different items on the triboelectric series and there was no reaction. I'm not sure how to fix this, can you help?

Hi Jack - this project can be a tricky one because it's easy to accidentally dissipate the static charge on objects, for example by touching them, placing them on a surface that's too conductive, or even if you're just in an area with humid air. Have you tried the project in a few different locations? You can also try holding the circuit and walking around with it while pointing the resistor at different objects.

I did end up trying that luckily I figured out the problem was with the transistor. I was using one I had at home which had a different gate location the one assigned in the projects instructions. I was able to fix it by switching some wires around. Thank you for your response though I appreciate it!

Ah, sorry, I assumed you were using the exact parts linked in the project. Yes, when switching parts it's always important to double check as they may not be a pin-for-pin match. Glad you got it working!