12. A single conductor in a power transmission line is 40 m long and carries a conventional current of 80 A from east to west. It lies perpendicularly across the Earth's magnetic field somewhere in Canada. If the Earth's magnetic field is 2.0 x 10"T, what is the magnitude and direction of the deflecting force on the transmission line? 13. If a 45 mg conductor that is 15 cm long is accelerating upward (against gravity) at 4.19 m/s in a 5.0 mT magnetic field, how much current must be flowing in the conductor? (0.84 A) 14. Three particles move through a constant magnetic field and follow the paths shown in the drawing. Determine whether each particle is positive, negative, or neutral. Give reasons for your answers. 15. Three particles have identical charges and masses. They enter a constant magnetic field and follow the paths shown in the picture. Which particle is moving fastest, which is moving slowest? Justify your answer. 16. A magnesium ion (Mg"*) traveling at 60 000 m/s enters a mass spectrometer with a magnetic field of 0.0800 T at an angle of 90" to the field and has a radius of 9.46 x 102 m. What is the mass of the magnesium ion? 17. An alpha particle with a speed of 4.4 x 105 m/s moves perpendicular to a 0.75 T magnetic field in a circular path. Determine the radius of the alpha particle. 18. A mass spectrometer uses a potential difference of 2.00 kV to accelerate a singly charged ion. Then, a 0.400 T magnetic field bends the ion into a circular path of radius 0.226 m. What is the mass of the ion?W 19. A positively charged sphere is suspended between two large metal piates as shown in the diagram. A wire is placed between the poles of a horseshoe magnet and connected to the metal plates. when the wire is drawn horizontally to the right the charged ball is observed to swing toward the right-hand metal plate. A. Determine the direction of the induced electron flow in the wire in the horseshoe magnet. Justify! I.I'our answer. B. Is the top pole of the magnet a north pole or a south pole? JustifyI your answer. 20. A magnet is moved relative to a coil of wire, inducing a conventional current shown in the diagram below. Determine the direction the magnet is moving. PHYSICS DATA SHEET Constants Prefixes Used with SI Units Particles Acceleration Due to Gravity Exponential Charge Mass Near Earth........ lag| = 9.81 m/$2 Prefix Symbol Value Gravitational Constant ...... G =6.67 x 10-1 N-m2/kg2 .. 10-18 Alpha Particle....... +2e 6.65 x 10-2 kg atto ..... .. a ...... Radius of Earth ... ......". Me = 6.37 x 100 m femto ....... f ..............10-15 Electron ..... 9.11 x 10 3 kg Mass of Earth ........ ............. Me = 5.97 x 1024 kg pico............ P.......... 10-12 Proton ..... ...... +le 1.67 x 10 kg Elementary Charge ....... e = 1.60 x 10-19 C nano... .... n.. 10-9 Coulomb's Law Constant .. k = 8.99 x 109 N.m3/C2 micro ...... H ............. 10-6 Neutron..... 0 1.67 x 10-27 kg Electron Volt ...... 1 eV = 1.60 x 10-19 J milli......... m.............10-3 First-Generation Fermions Index of Refraction of Air. n = 1.00 centi..... C........... 10-2 Charge Mass Speed of Light in Vacuum. c= 3.00 x 10 m/s deci.... ...10-1 Electron .... ~0.511 MeV/c2 Planck's Constant ........... h = 6.63 x 10-34 J.s deka ............ da......10' h = 4.14 x 10 eV.s hecto ........ h..............102 Positron ..... ~0.511 MeV/c2 Atomic Mass Unit .......... u = 1.66 x 10 2kg kilo ....... K.......... 103 Electron neutrino, V..... 0