Roentgen (unit) absorbed dose in a wide range of matter. When measuring absorbed dose in a human due to external exposure, the SI unit the gray, or the related non-SI rad are used. From these can be developed the dose equivalents to consider biological effects from differing radiation types and target materials. These are equivalent dose, and effective dose for which the SI unit sievert or the non-SI rem are used. The following table shows radiation quantities in SI and non-SI units: Roentgen (unit) The roentgen or röntgen () (symbol R) is a legacy unit of measurement for the exposure of X-rays
David Roentgen Gotha, exhibited at Callenberg Castle in Coburg, north Bavaria. In 2012 Wolfam Koepp of the Metropolitan Museum of Art discovered a particular type of Roentgen table with removable legs for easier transport. Was this table the earliest form of flatpack? A team from the Victoria and Albert Museum investigated further and confirmed Koepp's process and conclusions in March 2014, shedding new light on the inventor of flat-pack / ready-to-assemble furniture. Until then, Gillis Lundgren held that title from 1951 for IKEA. Its blame has now been traced back 200 years before the pretender. David Roentgen not only mastered intrigue but