Eye Strain. When you stare at screens all day, your eyes can get tired. Take a break with the 20/20/20 rule. Look at an object at least 20 feet away for 20 seconds every 20 minutes, says Ivan Schwab, MD, a spokesman for the American Academy of Ophthalmology.
Once you have the dial on your volt meter set to measure voltage, simply touch the black lead to the negative (-) terminal on your battery and the red lead to the positive ( ) terminal on your battery.
Alternator output is measured in both voltage and amperage. To understand voltage and amperage, you must also know about resistance, which is measured in ohms. An easy way to picture this is to compare the movement of electricity to that of running water. Water flows through a pipe with a certain amount of pressure.