Schalldruckpegel berechnen, was ist Dezibel? (Akustik 02)

0:00 Introduction 0:15 Sound Waves 1:10 Sound Pressure 3:05 Hearing Threshold 4:30 Pain Threshold 5:55 Decibels 6:18 Sound Level 7:00 Calculating Examples What does "dB" mean and what does it have to do with volume? It's explained clearly here. Welcome to Physics with JanYellow. It's about acoustics, about calculating sound pressure in decibels. A loudspeaker, as a sound source, emits sound waves that create waves of alternating high and low pressure in the air. Each individual air particle moves back and forth, remaining in the same place. The fluctuation in the air density moves away from the sound source to the ear. There, the fluctuations in air pressure cause the eardrum to vibrate. The person then perceives the sound. Whether the sound is loud or low varies from individual to individual. Because every ear perceives every sound very subjectively, how can different volumes be objectively compared? Answer: through sound pressure. Sound always creates a pressure fluctuation – and "pressure" can be measured in Pascals. The greater the pressure difference between the thinner and denser air layers, the louder the sound.