Propagation of sound

Grade 7 (Physics)

1. PROPAGATION OF SOUND By: JENNY P. LAGUNA Science Teacher

2. SOUNDS are forms of energy…it consists of a waves

3. How do sound propagate or spread? It propagate through a…. MEDIUM …..Solids, Liquids, and Gases… SOLIDS are…..metals, woods, plastics, glasses LIQUIDS are….. water (fresh or salt), milk, mercury, oil, alcohol GASES are…. Air, oxygen, carbon dioxide, helium, hydrogen

4. SOUNDS are MECHANICAL WAVES …..need a medium to propagate. LONGITUDINAL WAVES … travels parallel to the motion of particles.

5. Sound travels through a medium, There are alternating regions, Compressions are high pressure regions where the molecules are crowded together. Rarefactions are low pressure regions where the molecules are more spread out.

6. Sound travels through a medium, In solids , sound travels fastest-the molecules are very close to each other. In liquids , sound travels faster than gas because the molecules are close to each other. In gases , sound travels slowest because the molecules are far apart.