Science Buddies: "Ask an Expert"

My project is due in 5 days and I need a multimeter to measure how much voltage my "coin battery" can produce but I have no clue as to which one I should buy and how to use it. Any help?

Depending where you are, multimeters are available in all sorts of stores these days. I can't suggest any specific meter that you'll definitely be able to walk into a store and buy. Radio Shack sells decent enough meters, many box stores (Walmart, Lowe's, Home Depot) sell them in their auto parts or electrical sections.

You don't need the most expensive one they sell. A good meter with AC or DC voltage ranges starting at 2V and resistance (Ohms) can be found for $15 at the box stores. When you spend a little more you also get better accuracy and perhaps more precision. If you plan to continue using the meter to explore, I'd suggest you look to spend between $25 and $50 at a minimum. The meters I trust for making measurements when I'm designing or repairing something all tend to cost at least $150 - they're more accurate and that can matter when you're designing delicate circuits.

With only 5 days to go you don't have time to order anything from the internet. Personally, I like meters from Fluke, B&K Precision, and have had good luck with inexpensive Extech meters. There are many others as well. Once you get one if you need help getting used to it, you might find our tutorial (https://www.sciencebuddies.org/science- ... rial.shtml) helpful.

jazminecoleman - For your experiment, a very basic multimeter will suffice. Beyond HowardE's recommendations, if you have access to a Harbor Freight store in your area, a simple unit is available for less than $5. The Science Buddies tutorial is very helpful in putting it to use. Here is the link.

http://www.harborfreight.com/7-function ... 98025.html

Rick Marz