Engineering, 29.08.2019 22:00 MsShreve9939

The sound pressure level at a particular location in an underground carpark is lp_1. when a car starts it engine, the sound pressure level at the same point is lp_2. what would be the sound pressure level (in db) at that point due to the car engine only? lp_1 (db) = 68; lp_2 (db) = 72.5;

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The sound pressure level at a particular location in an underground carpark is lp_1. when a car star...

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