Potentiometer, an electrical device that measures potential difference between two points in a circuit by comparison with a standard battery of known potential difference. The name is also applied to a variable resistor that provides varying amounts of potential difference.
About two-thirds of all adults partake in this mind-altering substance, yet many do not consider it a drug. But if you've ever seen someone who's had too much to drink, you know that alcohol has profound effects on the mind and body.
Criminals always leave traces behind after a crime is committed. In fact, footprints, tire tracks and tool marks are often more prevalent than fingerprints at a crime scene. What can impression evidence tell an investigator?