Mechanisms for interactions between ultrasound waves and materials vary as a function of input power of ultrasound. The objectives of this study were to compare mode of actions for ultrasound waves at different input powers. This study also describes various effects of ultrasound on materials at different input powers with emphasize on food and polymer applications. At low power of ultrasound, the major mechanism is acoustic streaming and at a power above threshold value, the most possible one is acoustic cavitation. Low power of ultrasound is a powerful analytical technique to investigate on physico-chemical properties of both biological and non-biological materials. While at sufficiently high power, it generates shear forces that are able to create different effects. For each pair of medium-acoustic wave, two types of mechanisms, acoustic streaming and cavitation may be occurred simultaneously.