Measurements and Instrumentation - Section 1
Measurements and Instrumentation - Section 1
| 1. | In figure the bridge is balanced when Z4 is |
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| 2. | It is required to measure angular position. Out of the transducers 1.Circular potentiometer 2.LVDT 3.E pick up 4.Synchro The proper devices are
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Answer: Option D Explanation: LVDT and E pickup are suitable for linear displacement. |
| 3. | In two wattmeter method of 3 phase power measurement, when does one wattmeter read negative |
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Answer: Option C Explanation: When p.f. is less than 0.5 (leading or lagging) one of the wattmeters reads negative. |
| 4. | Loss of charge method is suitable for medium resistances. |
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Answer: Option B Explanation: It is suitable for high resistances. |
| 5. | A dynamometer wattmeter is connected in ac circuit. The measured power is |
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Answer: Option B Explanation: All wattmeters measure average power over a cycle. |
| 6. | Induction wattmeter can be used in |
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Answer: Option A Explanation: Induction effect occurs with ac only. |
| 7. | A moving iron instrument gives correct reading when used at |
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Answer: Option C Explanation: If frequency changes reactance of coil changes and reading is affected. |
| 8. | In a thermocouple temperature transducer, the output voltage is usually measured by |
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Answer: Option C Explanation: The output voltage is very small. So we need a milli voltmeter. |