1 The material is another important basis for computation of cost. 2  The material is usually computed by yard. 3  A couch on average uses from 18 to 22 yards of fabric. 4  Some fabrics cost as low as $15 per yard to as high as $180 for fabrics made of silk and wools. A couch on average uses from 18 to 22 yards of fabric. 2  Some fabrics cost as low as $15 per yard to as high as $180 for fabrics made of silk and wools. 3  Labor charges vary according to location and if the person doing it is a novice or professional for the job.
The major energy loss of high-energy (relativistic) electrons (energy greater than about 10 MeV, depending somewhat upon material) occurs from the emission of bremsstrahlung, and this is the major source of gamma rays in a high-energy cosmic-ray shower. See Electromagnetic radiation.
X-ray Tube. X-rays for medical diagnostic procedures or for research purposes are produced in a standard way: by accelerating electrons with a high voltage and allowing them to collide with a metal target. X-rays are produced when the electrons are suddenly decelerated upon collision with the metal target; these x-rays are commonly called brehmsstrahlung or braking radiation. If the bombarding electrons have sufficient energy, they can knock an electron out of an inner shell of the target metal atoms.