Exercise one, “Taste the Power” will probably have the electronic neophyte taken aback a bit. You’re literally preparing yourself for a taste of electronics. Don’t worry though, a 9-volt battery to your tongue is not as shocking as it may appear. Notably, the text regarding Ohm fundamentals and how a battery works is the emphasis of importance.
Exercise two “Let’s abuse a battery“. Here’s another project that may possibly cause concern to the uninitiated. Questions may rise such as, “Will the battery explode?”. Most likely not, but you always have to be careful and adorn safety eyewear, especially when working with electronics.
The first part of exercise two demonstrates how heat is generated as a result of electricity flowing through the battery cable wires and the electrolyte inside the battery. NOTE: make sure you are using an alkaline battery and not a rechargeable one.
The take away at least for me for this exercise is an attempt to answer the question, “How much current actually flowed through battery case wires before the battery shorted?” As per the material, attempting to measure the current with your DMM may blow its internal fuse. However, there are ways to properly measure current with your DMM, but it’s not covered here.
As an alternative to testing the amount of current with the DMM, we sacrifice a 3-amp fuse instead. Initially the 3-amp fuse I used was definitely much stronger than anticipated. I ended up connecting the battery wires directly to the fuse so it would blow. The take way here is to understand one of the roles of a fuse – protecting sensitive circuits.When the fuse breaks it prevents the flow of electricity to the rest of the circuit.
Overall, both of the labs are pretty simple and straight forward. These labs provide some valuable information to the beginner venturing into electronics. More importantly, learning is always fun. Baby steps…
1.5v AA battery (2)
AA battery carrier
Magnifying glass / Jewelers loupe
DMM (Digital Multi-meter) w/leads