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PES 1120 General Physics II Practice Exam 3 One (3” x 5”) index card may be used for formulas or other notes or diagrams. Definitions & Concepts 1. Magnetic force on an electron traveling through a uniform magnetic field, B, as shown in the given diagram. What direction is the electron traveling? a. b. c. d. B F Up Right Into page Out of page 2. What units result from multiplying ohms and farads? 3. What is the value of the line integral ∮ ⃗ ⃗⃗⃗⃗ about the Amperian loop shown? Applications 4. Determine the voltage and current for the 8 resistor. 5. A capacitor of capacitance 12F and a resistor of 50 and a switch are connected in series with a battery of voltage 10V. How long after the switch is closed does it take for the charge in the capacitor to reach half of its maximum amount? R. Gist 1 of 2 Long Semester Ver. A, Rev 3 PES 1120 General Physics II Practice Exam 3 6. A charged particle (charge = 5.0 µC) moves in a region of a 9 mT magnetic field directed along the vector (2/3 i +1/3 j – 2/3 k). The particle’s velocity is specified by (3000 m/s)i + (4000 m/s)j. What is the magnetic force vector on the particle? 7. A straight wire carries a current of 40 A in the region of a uniform magnetic field that is oriented perpendicular to the wire. If the force per unit length on this wire is 2.0 N/m, determine the magnitude of the magnetic field. 8. The figure shows the orientation of a rectangular coil consisting of 80 closely wrapped loops or turns each carrying a current of 8.0 A. The magnetic field in the region is 50 mT along the x-axis. The coil is hinged so that it can turn about the y axis. If = 30, a = 0.40 m, and b = 0.30 m, what is the magnitude of the torque exerted on the coil? 9. What will be the radius of curvature (cyclotron radius) of the path of a proton (mass=1.67 x 10-27 kg, charge=1.602 x 10-19 C) with a kinetic energy of 3.0-keV (1eV=1.602 x 10-19 J) in a perpendicular magnetic field of magnitude 0.40 T? 10. Two long parallel wires are separated by 4.0 cm. One of the wires carries a current of 20 A and the other carries a 30 A current in the same direction. Determine the magnetic force per unit length experienced by the wire carrying the greater current. 11. A long solenoid is wound with 960 turns per meter of thin wire through which a current of 300 mA is maintained. What is the magnetic field strength at the center of the solenoid? R. Gist 2 of 2 Long Semester Ver. A, Rev 3