| Voltage Multipliers | ||||||||
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| R | = | multiplier resistance in ohms, | ||||||
| Efs | = | full scale reading required in volts, | ||||||
| Ifs | = | full scale current of meter in am- | ||||||
| peres, | ||||||||
| RM | = | meter resistance in ohms | ||||||
| Measuring Resistance | ||||||||
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| with Milliammeter and battery* | ||||||||
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| RX | = | unknown resistance in ohms, | ||||||
| RM | = | meter resistance in ohms, or effec- | ||||||
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tive meter resistance if a shunted
range is used, |
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| I1 | = | current reading with switch open, | ||||||
| I2 | = | current reading with switch closed, | ||||||
| RL | = | current limiting resistor of suffi- | ||||||
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cient value to keep meter reading
on scale when switch is open |
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*Approximately true only when current limiting
resistor is large as compared to meter resistance. |
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| Measuring Resistance--(Continued) | ||||||||
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| with Milliammeter, Battery and Known Resistor | ||||||||
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| RX | = | unkown resistance in ohms, | ||||||
| RY | = | kown resistance in ohms, | ||||||
| RM | = | meter resistance in ohms, | ||||||
| I1 | = | current reading with switch closed, | ||||||
| I2 | = | current reading with switch open, | ||||||
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| with voltmeter and Battery | ||||||||
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| RX | = | unkown resistance in ohms, | ||||||
| RM | = | meter resistance in ohms, including | ||||||
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multiplier resistance if a multiplied
range is used, |
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| E1 | = | voltmeter reading with switch closed, | ||||||
| E2 | = | voltmeter reading with switch open, | ||||||
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