Please answer the following questions What effect does connecting the ammeter an
ID: 1551622 • Letter: P
Question
Please answer the following questions What effect does connecting the ammeter and voltmeter into the circuit have on the experimental results? Why must the ammeter and voltmeter be set on the lowest possible scale selling in order to obtain the most accurate results? Suppose a current significantly larger than 100 mA were passed through a resistance spool for a long period of time. What effect, if any, would this have on the resistance of the spool? Which of the following materials has the smallest resistivity? (a) aluminum, (b) copper, (c) German (nickel) silver, (d) gold, (e) iron, (f) lead. Why are two wires connected to a resistor in a circuit, instead of a single wire?Explanation / Answer
1. An ideal ammeter withdraws a little voltage, so offer almost no resistance but a practical ammeter do cause some voltage drop across it , so introducing some resistance in circuit. To obtain best experimenta results ammeter should be connected in series in circuit so that it have little effect on current.
In voltmeters when placed in parallel withdraws current from circuit, they are made of high resistance so that almost no current flows through them but more current flows through circuit itself.
2. Initially both instruments are set at their maximum range, then it is changed to lowest range so that pointer moves maximum distance. By measuring this large distance , even smaller fluctuations can be measured, thereby obtaining accurate results.
4. copper has smallest resistivity amongst these.
although silver has this property but here is nickel silver which has high resistivity.
5. Since current entering resistor should also leave, ofcourse it can be stored inside resistor, so one lead is for entrance and other is for exit.