Question

Numerical Circuit Simulations and Oscilloscope Measurements

PART III: In as few words as possible, but still using complete sentences and grammatically correct Standard English, explain how the total current through the device was measured and why, experimentally, it was measured this way.

• HINT 1: Think about the value of the resistor used to measure the current, the value of what would be considered “the load”, and think what a “perfect” measurement of a current through any load would be.

• HINT 2: What you submit for the writing section for grading would not typically be the first draft of your work. Carefully and thoughtfully edit your own work before submitting it.

Answer 1

Current is the measure of the rate of electron “flow” in a circuit. It is measured in the unit of the Ampere, simply called “Amp,” (A). The most common way to measure current in a circuit is to break the circuit open and insert an “ammeter” in series (in-line) with the circuit so that all electrons flowing through the circuit also have to go through the meter. Because measuring current in this manner requires the meter be made part of the circuit.

When an ammeter is placed in series with a circuit, it ideally drops no voltage as current goes through it. In other words, it acts very much like a piece of wire, with very little resistance from one test probe to the other. Consequently, an ammeter will act as a short circuit if placed in parallel (across the terminals of) a substantial source of voltage. If this is done, a surge in current will result, potentially damaging the meter

Ammeters work to measure electrical current by measuring the current through a set of coils with a very low resistance and inductive reactance. Connect an ammeter in series when measuring the current of a circuit. The low impedance of the ammeters means it won't lose much power.