In general, if a sound has intensity of β db at 1 m from the source, at what distance from the source would the decibel level decrease to 0 db? since the limit of hearing is 1 db this would mean you could no longer hear it. express the answer in terms of β. possibly relevant information: the sound of normal breathing is not very loud, with an intensity of about 11 db at a distance of 1 m away from the face of the breather. again: express the answer in terms of β!

The eel has a certain amount of rotational kinetic energy when spinning at 14 spins per second. if it swam in a straight line instead, about how fast would the eel have to swim to have the same amount of kinetic energy as when it is spinning?

At a certain instant after jumping from the airplane a, a skydiver b is in the position shown and has reached a terminal (constant) speed vb = 52 m/s. the airplane has the same constant speed va = 52 m/s, and after a period of level flight is just beginning to follow the circular path shown of radius ρa = 2330 m. (a) determine the velocity and acceleration of the airplane relative to the skydiver. (b) determine the time rate of change of the speed vr of the airplane and the radius of curvature ρr of its path, both as observed by the nonrotating skydiver.

The three classes of rocks are sedimentary, metamorphic, and igneous. how are rocks classified into one of these three groups?