How many times have you gone to stick batteries in a toy/radio/whatever to find that they’re dead and not known which is the dud and which is good? How do you test if your alkaline batteries are good or bad?
Thankfully this very clever trick will have you working it out in no time flat!
Rather than a multimeter which measures the current in the battery, this clever trick will save the hassle and allow you to find out anywhere, anytime.
Watch below and be impressed!