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.
A voltmeter is used to measure potentials as shown in Figure 1. The voltmeter has two clips that are colored red and black. When the red clip is connected to the anode and the black clip is connected to the cathode, a positive voltage is detected as shown in Figure 1. If the clips are backwards, a negative voltage is detected. In order to practice using the voltmeter, you can measure the potential of a closed battery. Turn on the meter and if it is not set to voltage push the + button once or twice. 1) Measure the potential difference of a AA (1.5 V) battery.