Two electronic oscillators are making some sine waves, at frequencies f1 = 882 hz and f2 = 880 hz. at a certain point, the sound level from one alone would be sil 1 = 76 db, and from the other sil 2 = 82 db. how often do beats occur

As we know that when two sound sources of slightly different frequency sound together then we will have resultant sound intensity changes with time

this is known as Beats

in order to find the beat frequency we will use

here we know that

now here we know that from above formula

now from this equation we can say that we will hear 2 beats per second

so time interval between two beats is given as

here we know that ball will drop down by total distance 3.2 m

so here we know that

now using kinematics

now in the same time it will cover horizontal distance of 0.75 m

so speed of the ball will be

ice to water 1 water to vapour 2 latent heat