A square, conducting, wire loop of side L, total mass m, and total resistance R initially lies in the horizontal xy-plane, with corners at 1x, y, z2 = 10, 0, 02, 10, L, 02, 1L, 0, 02, and 1L, L, 02. There is a uniform, upward magnetic field BS= Bk n in the space within and around the loop. The side of the loop that extends from 10, 0, 02 to 1L, 0, 02 is held in place on the x-axis; the rest of the loop is free to pivot around this axis. When the loop is released, it begins to rotate due to the gravitational torque. (a) Find the net torque (magnitude and direction) that acts on the loop when it has rotated through an angle f from its original orientation and is rotating downward at an angular speed v. (b) Find the angular acceleration of the loop at the instant described in part (a). (c) Compared to the case with zero magnetic field, does it take the loop a longer or shorter time to rotate through 90? Explain. (d) Is mechanical energy conserved as the loop rotates downward? Explain.

Day 1 1/4/2016 Mondays 56:30 Sections with the Professor Adriane Steinacker First Homework posted this Friday Lectures are Webcast Login: phys5b Password: Y0ung2sl1t Class Materials: rulers, compass, scientific calculator Yellow is her favorite color 1) Density (mass density) lett rho ρ ρ = mass over volume [ρ] = kg v m3 1 L (Liter) = 100cm 1m3 = 1000L 1 g kg converting 1 cm3= m 3 Assume air is made of Nitrogen molecules N atomic mass z = 7 7 protons and 7 electrons 2 A = 14 so 7p & 7e Mass of proton = 1.67 x 10 27 Mass of neutron = M p MN2 x 14 x 1.67 x 10