MCAT Physics Topical Practice Tests: Electrostatics & Magnetism 24. An amp is a unit of electrical: A. capacity B. current C. potential difference D. charge 25. A loop of wire is rotated about a diameter (which is perpendicular to a given magnetic field). In one revolution, the induced current in the loop reverses direction how many ti A. 2 B. I c. 0 D. 4 26. Two charges ( 2.310* C and -2.5 x 10 C) are a distance 0.1 m apart. How much energy is required to bring them to a distance 0.01 m apart? (Use Coulomb’s constant k 9 x 10 N-m/c2 C. 1.7 x 10J D. 4.7 x 10- J A, 2.2 x 10 B. 8.9×10 27. A solid aluminum cube rests on a wooden table in a region where a uniform external electric field is directed straight upward. What can be concluded regarding the charge on the top surface of the cube? A. The top surface is neutral B. The top surface is charged negatively C. The top surface is charged positively D. The top surface’s charge cannot be determined without further information 28. A point charge of +0 is placed at the center of an equilateral triangle, as shown. When a second charge of +9 is placed at one of the triangle’s vertices, an clectrostatic force of 5 N acts on it. What is the magnitude of the force that acts on the center charge when a third charge of+ is placed at one of the other vertices? 29. In the figure below, the charge in the middle is fixed and –7.5 nC. For what fixed, positive charge qi will non-stationary, negative charge q2 be in static equilibrium? A. 53 nC B. 7.5 nC C. 15 nC D. 30 nC 10 cm 10 cm 30. Which form of electromagnetic radiation has the highest frequency? A. Gamma radiation B. Ultraviolet radiation C. Visible light D. Radio waves Copyright 0 2018 Sterling Test Prep. Any duplication is illegal. 131