The primary responsibilities of human resources are: 1  C - Compensation. 2  H - Human resource development. 3  E - Employee and labor relations. 4  S - Safety and health. 5  S - Staff.
A new technique uses sound waves to levitate objects and move them in mid-air. Credit: Dimos Poulikakos View full size image. View full size image. Hold on to your wand, Harry Potter: Science has outdone even your best Leviosa! levitation spell.
We hear sound because vibrating particles vibrate our eardrums and our brain translates those vibrations into sound. 1. If sound is a form of energy, whatâs moving? 2. All sound comes from what? 3. What kind of a wave is sound? 4. What does frequency have to do with sound? 5. What does amplitude have to do with sound? 6. What made the balloon vibrate when we played sound over the speakers? Answers . 1. Energy is the ability to move something against a force. In the case of sound, molecules are moving. 2. Vibrations. No vibration, no sound. 3.