Radioactive Decay is Random

Radioactive decay is both random over space and time, and radioactive decay is spontaneous. Random Random over space means that given a large number of radioactive nuclei, it would be impossible to predict which nuclei would decay next. Random over time means that you cannot predict when a nuclei would decay at any time. Given a large number … Read more Radioactive Decay is Random

Ultrasound Intensity Reflection and Attenuation

Intensity Reflection Coefficient When a beam of ultrasound is directed into a body, a certain proportion of the initial intensity would be reflected at the boundary. The ratio of the reflected intensity to the initial intensity can be obtained using the formula Air-Tissue Boundary Using the formula from above, we can calculate that the intensity … Read more Ultrasound Intensity Reflection and Attenuation

Ultrasonic Production and Detection

Production Sound is created when a surface vibrates, pushing the medium particles into a series of compressions and rarefactions. A human being would normally be able to hear sound with frequency between 20 Hz and 20000 Hz. A piezo-electric  crystal is able to expand or contract according to the applied voltage. If an alternating current is … Read more Ultrasonic Production and Detection