QUIZ 1. What are the units for the ampere in physics? a. Coulombs per second b. Joules per second c. Charge per meter squared d. Volts per meter Answer: a. The units for ampere involve the change in charge over the change in time, which are coulombs per second. 2. In any electrical situation, which charges flow and in which direction? a. Only negative charges flow from negative to positive. b. Only positive charges flow from positive to negative. c. Both negative and positive charges flow from their highest energy level to the lowest energy level. d. Either positive or negative charges, or both can flow, depending on the electrical situation. Answer: d. In metal electrical circuits, only negative charge flows. In ionic and biological systems both negative and positive charges flow, while the flow in van de Graaf generators, is of positive charges only. 3. When we think of flow of electrons, what is true of the density of electrons and their drift velocity? a. The density will be directly proportional to the drift velocity. b. The density will be inversely proportional to the drift velocity. c. The density will be inversely proportional to the square root of the drift velocity. d. The density will be unrelated to the drift velocity. Answer: b. The density of electrons will be inversely proportional to the drift velocity in that, the greater the density of electrons, the more the
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