A 560 Hz tuning fork and a piano key are struck together, and four beats are heard. When a 572 Hz tuning fork and the same piano key are struck, eight beats are heard. What is the frequency of the piano key? 564 Hz
556 Hz
572 Hz
560 Hz

The rigid beam is supported by the three suspender bars. bars ab and ef are made of aluminum and bar cd is made of steel. if each bar has a cross-sectional area of 450 mm2, determine the maximum value of p if the allowable stress is (σallow)st = 200 mpa for the steel and ( σallow)al = 150 mpa for the aluminum. est = 200 gpa and eal = 70 gpa.

Akg a of 55 m at an of 11 ? . if is at 98 km/h, be ?

When a vertical beam of light passes through a transparent medium, the rate at which its intensity i decreases is proportional to i(t), where t represents the thickness of the medium (in feet). in clear seawater, the intensity 3 feet below the surface is 25% of the initial intensity i0 of the incident beam. what is the intensity of the beam "10" feet below the surface? (give your answer in terms of i0. round any constants or coefficients to five decimal places.)