In DC potentiometer measurments, a second reading is often taken after reversing the polarities of the DC supply and the unknown voltage and the average of the two reading is taken. This is with a view of eliminate the effects of Stray magnetic fields. Ripples of the DC supply. Stray thermal emfs. Errorneous standardisation. TRUE ANSWER : ? YOUR ANSWER : ?
The expected value of the voltage across a resistor is 80 V, and the measured value is 79 V. What is the percentage error and relative accuracy of the measurement ? 1.5% & 98.75% 1.25% & 98.25% 1.25% & 98.75% 1.5% & 99% TRUE ANSWER : ? YOUR ANSWER : ?
A voltmeter has 100 scale divisions and can measure up to 100 V. Each division can be read to ½ division. The resolution of the voltmeter is 1.5 V 0.5 V 1 V 2 V TRUE ANSWER : ? YOUR ANSWER : ?
Which of following voltmeters would you use for measuring voltage across 20KΩ resistance Voltmeter having a resistance of 5 ΩK. None of above. Voltmeter having sensitivity of 1 KW/V. Voltmeter having sensitivity of 10 KW/V. TRUE ANSWER : ? YOUR ANSWER : ?
Which one the following statements is correct? The application of the instrument in wrong manner in the procedure of measurement results in a/an instrument error random error gross error systematic error TRUE ANSWER : ? YOUR ANSWER : ?
In a portable instrument , the controlling torque is provided by Spring All of the listed here Eddy currents Gravity TRUE ANSWER : ? YOUR ANSWER : ?
The power factor of a single phase load can be calculated if the instruments available are Any of the listed here One voltmeter, one ammeter and one wattmeter One voltmeter and one ammeter One ammeter, one voltmeter and one energy meter TRUE ANSWER : ? YOUR ANSWER : ?
No eddy current and hysteresis losses occur in PMMC instruments Electrostatic instruments Electrodynamo meter instruments Moving iron instruments TRUE ANSWER : ? YOUR ANSWER : ?
Most sensitive galvanometer is Duddle galvanometer Elastic galvanometer Spot ballastic galvanometer Vibration galvanometer TRUE ANSWER : ? YOUR ANSWER : ?
Consider the following statement - 1. The compensating coil of a low power factor wattmeter compensates the effect of the impedance of the current coil. 2. The compensating coil of a low power factor wattmeter compensates the effect of the impedance of the voltage coil circuit. 1 is false but 2 is true. Both 1 and 2 are true. Both 1 and 2 are false. 1 is true but 2 is false. TRUE ANSWER : ? YOUR ANSWER : ?