.13 A strip of copper 150 um thick and 4.5 mm wide is placed in a uniform magnetic field B of magnitude 0.65 T, with B perpendi- cular to the strip. A current / = 23 A is then sent through the strip such that a Hall potential difference V appears across the width of the strip. Calculate V. (The number of charge carriers per unit vol- ume for copper is 8.47 x 1028 electrons/m3.) 13) n problem 13, solve for the Hall voltage (in microVolts) that would be generated if 7.5 Amperes of current are used to probe the material. 5 sig figs