2. A common physics experiment involves lowering an open tube into a cylinder of water and moving the tube up and down to adjust the length of the air column in the tube. A tuning fork of frequency 330 Hz is sounded and held at the upper end as the tube is lifted out of the water until the first resonant sound is heard. The length of tube above the water level when the fundamental note sounds is 26 cm. a. Calculate the speed of sound in the air column in the tube. b. Determine another position for the tube that will result in a resonance with this tuning fork. c. Determine the first position (as we again lower the tube into the water) that will resonate with a 256 Hz tuning fork.

To understand the electric potential and electric field of a point charge in three dimensions consider a positive point charge q, located at the origin of three-dimensional space. throughout this problem, use k in place of 14? ? 0. part adue to symmetry, the electric field of a point charge at the origin must point from the origin.answer in one word.part bfind e(r), the magnitude of the electric field at distance r from the point charge q.express your answer in terms of r, k, and q. part cfind v(r), the electric potential at distance rfrom the point charge q.express your answer in terms of r, k, and q part dwhich of the following is the correct relationship between the magnitude of a radial electric field and its associated electric potential ? more than one answer may be correct for the particular case of a point charge at the origin, but you should choose the correct general relationship. a)e(r)=dv(r)drb)e(r)=v(r)rc)e(r)=? dv(r)drd)e(r)=? v(r)r