REDMOND WA in Software

Printing QR in Software REDMOND WA

By now you are probably expecting me to tell you that our 50 A ammeter can be modi ed to measure resistance as well. You are correct. To measure the resistance of a resistor or other circuit load, we must isolate that component from the rest of the circuit. (Review the practice problems in 1 if you don t remember why.) Sometimes we can open a switch; sometimes we can disconnect a terminal; sometimes we have to unsolder one end of the component. Regardless of how we isolate the item, we measure its resistance indirectly by applying a test voltage and measuring the resulting current. Because zero resistance (a possibility in case of a short circuit inside the component) would draw a possibly destructive high current, we place a known current-limiting resistor in series with the meter. Figure 2.4 shows our ohmmeter. Inside its case are our same 50 A ammeter, a 1.5-volt battery, and a series resistor, RR. Maximum current will ow, and the meter will de ect full scale, when the resistance being tested, RL, is zero. From Ohm s Law:

experience within the larger context of a game. As with Visual Design, the emphasis is on design fundamentals rather than on specific technical knowledge.

Part I:

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If x < 3 then the function is plainly continuous. The function is undefined at x = 3 so we may not even speak of continuity at x = 3. The function is also obviously continuous for 3 < x < 4. At x = 4 the limit of g does not exist---it is 1 from the left and 11 from the right. So the function is not continuous (we sometimes say that it is discontinuous) at x = 4. By inspection, the function is continuous for x > 4.