Measurements and Instrumentation Questions

• To increase Q factor of a coil, the wire should be
• The Lissajous pattern observed on screen of CRO is a straight line inclined at 45° to x axis. If X-plate input is 2 sin ωt, the Y-plate input is
• The angle δ for a mica capacitor is about
• A voltmeter using thermocouples measures
• Which of the following statement is correct for two wattmeters method of power measurement in 3 phase circuit?
• In a CRO which of the following is not a part of electron gun
• The coil of a moving iron instrument has a resistance of 500 Ω and an inductance of 1 H. It reads 250 V when a 250 V dc is applied. If series resistance is 2000 Ω, its reading when fed by 250 V, 50 Hz ac will be
• In a ballistic galvanometer, a charge of 100 μC gives a first swing of 25°. The charge required to cause first swing of 50° is
• In a strain measuring device using a strain gauge, the output quantity is
• Magnetic flux density has the dimensions
• A dynamometer wattmeter is connected in ac circuit. The measured power is
• A meter with a resistance of 100 Ω and a full scale deflection of current of 1 mA is to be converted into voltmeter of 0 - 5 V range. The multiplier resistance should be
• A dynamometer wattmeter is connected in ac circuit. The reading will be
• In figure the bridge is balanced when Z4 is
• Which of the following voltmeters would you use for measuring voltage across 20 kΩ resistance?
• Potentiometer method of dc voltage measurement is more accurate than direct measurement using a voltmeter because
• In a thermocouple temperature transducer, the output voltage is usually measured by
• A digital frequency counter can be converted to DVM by addition of a suitable
• Assertion (A): When a wattmeter is used for low impedance loads, the pressure coil is connected across the load. Reason (R): A wattmeter measures apparent power.
• In which of the transformer is the secondary nearly short circuited under normal operating conditions?