Winds NNE at 9 mph (14.5 kph). The overnight low will be 41 Â°F (5.0 Â°C).Cloudy with a high of 62 Â°F (16.7 Â°C). Winds variable at 9 to 11 mph (14.5 to 17.7 kph). 50%58Â°47Â°Rain today with a high of 58 Â°F (14.4 Â°C) and a low of 47 Â°F (8.3 Â°C). There is a 50% chance of precipitation.
The amount of filtration of the x-ray beam is specified by and based on the voltage potential (keV) used to produce the beam. The thickness of filter materials is dependent on atomic numbers, kilovoltage settings, and the desired filtration factor.
xray of a scull image by alma_sacra from Fotolia.com. Compensating filters are used to even out the density (darkness) of the radiograph (X-ray image) when you are examining body parts with great variation in thickness.