What is the average energy of a Cs-137 source?

The average energy of a Cs-137 (Cesium-137) source is approximately 660 keV. This is significant in radiographic testing, as Cs-137 is commonly used as a gamma radiation source due to its specific energy characteristics and half-life of about 30 years. The energy level of 660 keV makes it suitable for penetrating different materials without excessive attenuation, thereby producing quality radiographic images.

In the context of radiographic testing, understanding the energy of the radiation source is crucial, as it affects the choice of exposure settings, the type of film used, and the quality of the radiographic interpretation. The energy level directly influences how well the radiation can penetrate different thicknesses and densities of materials, which is paramount in ensuring accurate results during inspections.

Other options provided, while close, do not reflect the average energy level for a Cs-137 source with the same accuracy, highlighting the importance of using the correct parameters to optimize radiographic outcomes.