Santa Rosa Junior College

• PHYS 0585

• PHYS 21 Exam 1 Fall 2019 Name: ___________________________________ Part I: Conceptual/quick calculation questions (10 points total) Each question below has only one correct answer. Each is worth 2 points. Circle the correct answer or fill in the blank. 2. An electron is initially moving to the right when it enters a uniform electric field directed upwards. Which trajectory shown below will the electron follow? 3. Under electrostatic conditions, the electric field just outside the surface of any charged conductor A. is always parallel to the surface. B. is always zero because the electric field is zero inside conductors. C. is always perpendicular to the surface of the conductor. D. is perpendicular to the surface of the conductor only if it is a sphere, a cylinder, or a flat sheet. E. can have nonzero components perpendicular to and parallel to the surface of the conductor. 4. The drawing shows the circular paths of an electron and a proton. These particles have the same charge magnitudes, but different masses. They travel at the same speed in a uniform magnetic field that is directed into the page everywhere. The magnetic field is strong enough so that the interaction between the proton and the electron can be ignored. Under each circle write which particle does it correspond to. Particle: _____________ ______________ 5. A parallel plate capacitor is connected to a battery that maintains a constant potential difference across the plates. Initially, the space between the plates contains only air. Then, a dielectric material (k = 2.1) is inserted between the p