Measurements and Instrumentation Questions

• A single phase energy meter has the rating 1200 resolutions/ kWh. If a 500 W electric gadget is used for 4 hours, the energy meter will make
• If reference sound pressure P0 is 2 x 10-5 N/m2, a sound pressure of 90 dB is equal to
• Assertion (A): A hot wire ammeter has a cramped scale. Reason (R): The heat is proportional to square of current.
• Consider the following statements: In a differential amplifier using JFET, the differential output offset is due to mismatch between FET parameters difference in values of resistances used in circuit variation in supply voltage. Of the statements, the correct statements are
• A full wave rectifier type meter is used to measure the wave shape shown in figure. The voltmeter is calibrated to read rms value of sine wave. The reading of voltmeter will be
• A moving iron instrument gives correct reading when used at
• Loss of charge method is suitable for medium resistances.
• Which of the following is true about an impulse voltage?
• In a resistance strain gauge, G = 2, stress = 1050 kg/cm2, R = 1000 Ω. The value of ΔR will be
• In 3 phase power measurement by two wattmeter method, the reading of one wattmeter is zero. The power factor of load is