How many atoms make up one kilogram of high-purity silicon? Researchers at the National Metrology Institute of Germany (PTB) are currently trying to find the answer. The number of atoms is intended to be the new reference value for the kilogram unit of measurement. This is necessary because the International Prototype of the Kilogram, a cylinder made from a platinum and iridium alloy kept in Paris, is gradually losing its mass.
Dynamic scales can measure things as they flash by - a scale by Wipotec for example, weighs 14,400 letters in one hour. The letters weighing up to 480 grams stand upright on a conveyor belt which runs over the weighing scales at a speed of 4 meters per second.
Lasers by Etalon can measure objects with an accuracy of one nanometer (0.000001 millimeter) and check whether a machine is positioned correctly.
The International Earth Rotation and Reference Systems Service measures the speed at which the earth rotates on its own axis. A leap second must be added every 500 to 750 days as this speed is continuously decreasing. The last time this happened was the turn of the year 2016/2017 when (world) time stood still for one second.
There are many methods for measuring human emotions, such as questionnaires, scanning facial expressions and recognition of intonation. The market research sector is particularly interested in results. Companies like Neurensics measures the brain activity of test persons using functional magnetic resonance imaging. (sno)