Middle C on a piano has a frequency of 262 Hz. Sometimes it is said that middle C is actually 28 = 256 Hz, and tuning forks are made with this frequency. How many beats per second would be heard if such a tuning fork were sounded simultaneously with the middle C of a (well-tuned) piano?

A5 foot by 5 foot box culvert is buried 6 feet beneath the surface of the ground. a crosssection of this very long culvert (into and out of the page) is illustrated below. assume that the soil in which the culvert is buried has the following properties: jt = 120 pcf, w = 12%, ko = 0.50, ka = 0.33, and kp = 3.00. calculate the total horizontal force per unit length of culvert (fh) felt on one of the vertical faces of the culvert.

Scientific models are based on current knowledge, which can limit their effectiveness when new discoveries are made.

Smallest intensity of a stimulus that you can detect 50 percent of the time is