The magnitude j of the current density in a certain wire with a circular cross section of radius r = 2.11 mm is given by j = (3.25 × 108)r2, with j in amperes per square meter and radial distance r in meters. what is the current through the outer section bounded by r = 0.921r and r = r?

These models show the electron structures of two different nonmetal elements. which element is likely more reactive, and why? element 1 is more reactive because it has fewer electron shells and is toward the top of its group on the periodic table. element 1 is more reactive because it has more electrons in its valence shell and is farther to the right on the periodic table. element 2 is more reactive because it does not have a valence shell close to the nucleus, so it will attract electrons. element 2 is more reactive because it does not have a full valence shell, so it will attract electrons.

Two identical 82 mg dust particles very far apart (pee 0) are moving directly toward each other at a speed of 3698 m/s. the charge on each is-719 ? c. determine how close they will get to each other. let k = 9x109 n-m2/c2 & ignore gravity.

Abug is 12 cm from the center of a turntable that is rotating with a frequency of 45 rev/min . what minimum coefficient friction is required so that the bug stays on the turntable?