Instrumentation amplifier employs how many opamps 3 What is the typical power range for thermocouple sensors?

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1 QUESTIONS ANSWERS Instrumentation amplifier employs how many opamps 3 What is the typical power range for thermocouple sensors? 0.1uW to 100mW The period of a repetitive signal is 1 cycle of the waveform An ammeter has a full-scale deflection current of 100mA. If the same ammeter is used to 10 ohms measure a full-scale current of 1.0ampere, what is the value of the shunt resistor in ohms if the voltage across the meter is 9.0 volts? A galvanometer with 20 ohms coil resistence has a full-scale deflection of 10 ma. A A ohm is placed across the meter to increase its rating capacity. What is the new full scale current for the meter? A certain pulse measures 10ms and has a period of 50ms. The duty cycle is 10ms/50ms = 20% meter is the most sensitive 1uA Calculate the shunt resistance needed to increase the FSD of an ammeter 5 times if the 250ohms meter resistance is 1kohm What should be the resolution of a digital voltmeter having three digit 0-3V? 3mV An ammeter with an internal resistance of 50 ohm(s) is used to measure a current thorugh 50/(50+1k)*100 = 4.76% a lod resistor Rl = 1 kohm(s). Determine the percentage error of the reading due to ammeter insertion. What is the typical full-scale deflection current of a moving coil instrument? 50mA What is the typical full-scale voltage across a moving coil voltmeter? 50mV Indications of spectrum analyzer is presented by means of a CRT An iron vane is used to measure AC What is the degree of exactness of measurement when compared to the expected value of Accurary the variable being measured? What damping method is generally used in dynamometers? air friction What damping method is generally used in dynamometers? air friction The pointer of an indicating instrument is generally made of aluminum An instrument used for measuring the amount of current flowing in a circuit. ammeter What is the basic unit for measuring current flow? ampere Which of the following forces does not act on the moving systems of analog instruments? an electrostatic force What kind of instrument is an ammeter? an indicating What type of instrument is the watt-hour meter? an integrating An instrument in which the magnitude of the measured quantity is indicated by means of analog instrument pointer. In measurements, the sum of a set of number divided by the total number of pieces of data arithmetic mean in the given set is called In order to make an accurate measurement as possible, the internal resistance of a as high as possible voltmeter must be On a simple ohmmeter, the 0 ohm(s0 mark is located of the scale at far right Indicating instrument is assumed to be most accurate at what part of the scale? at half or full A bridge wherein all legs are electrically identical balance bridge Error in ohmmeter is due to battery aging Error in ohmmeter is due to battery aging What is the reason why the scale of a permanent-magnet moving coil instrument is uniform? because it is spring controlled Dynamometer type instrument can be used for both dc and ac works What is this instrument or circuit that has four or more arms, by means of which one or bridge more of the electrical constance of an unknown component may be measured? In meter movement, how do oyu prevent the meter from oscillating and overswing? by damping How can electric currents be induced with a coil and a magnet? by moving either the magnet or the coil

2 Maxwell bridge measures an unknown inductance in terms of known An element of a CRT, that releases electrons when heated indirectly by a filament What provides a visual representation of any waveform applied to the input terminals? Considered as the "heart" of the cathode ray oscilloscope. Which of the items below describes an absorption meter's usage? Which of the ammeter below has no insertion error? What are the two most popular RF oscillators? What is the purpose of the rheostat in ohmmeter? The zero-adjust control in an analog type ohmmeter is used to What CRT element provides for controls of the number of electrons passing father into the tube? A moving system force in analog instruments which ensures that the deflection of the pointer for a given value of measured quantity always has the same value What is the force acting on the pointer of an indicating instrument when it is in motion? The provides the visual display showing the form of the signal applied as a waveform on the front screen of a cathode ray oscilloscope For a dynamometer to be able to measure high current, a should be used. What is the most common type of meter movement? If the pointer of an indicating instrument is in motion, then what opposes deflecting torque? A force in analog instrument which quickly brings the moving system to rest in its final position. Another name for PMMC instrument Which is the best type of ammeter movement? Where can we used the dynamometer? Basically, a PMMC instrument can be used only in Meters with moving coil are normally used for measuring Permanent-magnet moving coil instrument can be used in A moving system force in an analog instruments which causes the moving system to deflect from its zero position. To increase the measuring capability of a moving-iron ac ammeter, a should be used. What sensor provides a dc voltage approximately 1V at 10mW? A tunable RF instrument, which, by means of a sharp dip of an indicating meter, indicates resonance with an external circuit under test A type of meter that gives a precise reading of voltage, current or resistance where there is the generation of samples at the input and then feeds it to a digital read-out. A device used to mechanically measure the output power of a motor Which movement is the most expensive? An indicating instrument whose movable coils rotate between two-stationary coils, usually used as All voltmeters except one of the following are operated by the passage of current Measurement of high dc-voltages is usually done by using Which of the voltmeter is used for measuring high direct voltage (say 10kV)? Generally, oscilloscope uses what type of deflection? What is that meter that depends for its operation on the forces attraction and repulsion capacitance cathode cathode ray oscilloscope (CRO) cathode ray tube (CRT) check the output frequency of a transmitter clamp-meter Colpitts and Hartley compensate aging battery of the mter compensate for the differing internal battery voltage control grid controlling force controlling, damping and deflecting torques CRT current transformer D' Arsonval damping and controlling torque damping force D'Arsonval D'Arsonval dc and ac dc measurements dc only dc work only deflecting force different number of turns of coils diode sensor dip meter DMM dynamometer dynamometer electrodynamometer electrostatic electrostatic electrostatic electrostatic deflection electrostatic instrument

3 between electrically charged bodies? A common technique for measuring power at high frequency is to The deviation of a reading from the expected value A Kelvin electrostatic voltmeter uses what method of damping? What is being controlled at the potentials between anode of an oscilloscope? An element in electronics which serves as a protection against overload? An instrument used to detect and measure the presence of electrical current is generally called Tank-circuit frequency can be measured by Refers to an ac bridge for measuring the inductance and Q of an inductor in terms of resistance, frequency and a standard capacitance. What bridge is used to measure high-q inductors? (Q>10) An AC bridge that measures mutual inductance Voltage measurement in a high impedance circuit requires a voltmeter with High sensitive DC voltmeter provides accurate reading when measuring circuits. High sensitive DC voltmeter provides accurate reading when measuring circuits. An electro pyrometer is an instrument used to measure? For time measurements, scale of the scope is used. As the deflection of the moving system increases, the controlling torque in an indicating instrument. Decreasing the value of the shunt resistor of an ammeter, it current measuring capability The output voltage of a thermocouple What do you call of an instrument that depends for its operation on the reaction between magnetic flux set up by currents in fixed windings and other currents set up by electromagnet induction in movable conducting parts? What is the normal indication on a megger when checking insulation? Error in ammeter reading is due to A device or mechanism used to determine the value of a quantity under observation. Errors due to frictions of the meter movement, incorrect spring tension, improper calibration or faulty instruments: In an oscilloscope, adjusts the brightness of the spot by chaning the current on the control grid. A meter has a full-scale current of 50uA, what is its sensitivity? A bridge used to measure small resistances An electrostatic voltmeter in which an assembly of figure-8-shaped metal plates rotates between the plates of a stationary assembly when a voltage is applied betweeen the assemblies. A pattern displayed by oscilloscopes which has a steady characteristic is called Error in voltmeter is due to Determine which is not a dynamic instrument A is a device that can test all pins of an IC at the same time. Current range extension in moving coil instruments can be achieved by placing a in shunt with the instrument. Majority of analog measuring instrument utilizes one of the following effects. Type of power-line frequency meter device utilizing a principle of balancing an indicator needle at center of a scale using magnetic fields opposing each other. employ a sensing element that converts the RF power to a measureable dc or low-frequency signal error fluid friction Focus fuse galvanometer grid dip meter hay bridge hay bridge Heaviside bridge high input impedance high resistance high resistance high temperatures horizontal increases increases increases with temperature induction instrument infinity insertion instrument instrument errors intensity control Is=1/50uA=20kohm/V Kelvin Bridge Kelvin voltmeter Lissajous loading Logic logic clip low resistance resistor magnetic effect magnetic type

4 What is that instrument used for measuring the strength and direction of magnetic fields? Shunts are generally made of what material? This refers to a four-arm ac bridge used for measuring inductance against a standard capacitance. is used for measuring medium Q coils The art or process of determining the existence or knowing the magnitude of something, directly or indirectly in terms of a recognized standard Insulation resistance is measured by which meter? Resistance measuring instrument particularly used in determining the insulation resistance A operates on the magnetic attraction-repulsion principles. Attraction and repulsion instruments are considered as What is the device, which depends on the action of a movalbe permanent magnet, in aligning itself in the resultant field produced by a fixed permanent magnet or currentcarrying coils whose axes are displaced by a fixed angle? A bridge used to locate accidental grounds on communications and power lines When should a fuse be replaced with a higher rated unit? A device or instrument able to generate noise with accurate voltage for test purposes refers to garaging the two adjustments of an AC bridge together in such a way that changing in one adjustment change the other in a special way, but changing the second adjustment does not change the first An electronic measuring device that provide instantaneous visual indication of voltage excursions A meter when will become insensitive to small signals An AC bridge that measures inductance in terms of resistance and capacitance. An oscilloscope provides easy measurement of values. The interval of a pulse from start to end is the of the pulse Which instrument is the most sensitive? A material that glows when struck by the energetic electrons in a CRT Which electrical instruments below is the most sensitive? A measure of consistency or repeatability of measurements is called. It consists of a diode and an opamp and has the ability to clip low level signals It consists of a diode and an opamp and has the ability to clip low level signals The time interval between pulses is called The time interval that a waveform is high (or low) is the of the signal. This instrument measures temperatures by electric means, especially temperatures beyong the range of mercury thermometers Is a nucleonic sensing method employing usually one or more radioisotope sources and radiation detectors. Bridge used to measure both inductive and capacitive impedances at higher frequencies A type of photometer used to measure reflection. In RF and microwave system, what instrument is used to measure the incidental and reflected signals? Precision is also known as A four-arm bridge. All arms of which are predominantly resistive; used for measuring resistance The smallest change in a measured variable to which an instrument will respond. When both deflecting and controlling torque act, the pointer of an indicating instrument comes to Calculate the series resistance needed to convert a D' Arsonval meter with FSD of 100uA and a meter resistance of 1kohm to a voltmeter with 10V FSD. magnetometer manganin Maxwell Bridge Maxwell Bridge Measurement megger Megger/Megaohmmeter milliameter moving iron instruments moving-magnet instrument Murray Loop never noise generator orthogonal nulling oscilloscope overdamped Owen's Bridge peak to peak period permanen-magnet moving coil phosphor PMMC precision precision diode precision diode pulse delay pulse width pyrometer Radiation sensing radio-frequency bridge reflectometer reflectometer reproducibility Resistance Bridge and Wheatstone Bridge resolution rest Rs=10V/100uA - 1kohm = 99kohm

5 What do you call an oscilloscope that uses sampling techniques in processing signals having frequencies beyond its normal capabilities? Type of waveform generated by the sweep generator of the CRT Which of the following is not a basic part of a CRT? An AC bridge that measures capacitance and dissipation factor In VTVMS, refers to the smallest signal that can be reliably measured It is the reciprocal of the full-scale current of a meter A device or instrument, which delivers signals of precise frequency and amplitude, usually over a wide range Most AC voltmeters have an rms scale which is valid only if the input signal being measured is a signal. A simplified version of the Wheatstone bridge wherein, two of the ratio arms are replaced by a 100cm long Manganin of uniform cross-sections and provided with a slider What is an electronic instrument capable of showing on screen and maybe on print, relative spacing of transmitter carriers, their sidebands and harmonics? Controlling torque in PMMC Moving-iron instrument has a/an scale The scale of a hot-wire instrument is a/an function An instrument of device having recognized permanent of stable value that is used as a reference. Types of oscilloscopes that are able to retain the display for a longer period of analysis. This display is retained by the use of flood gun. The frequency of rotation in some rotating machinery can be measured by a In a moving coil ammeter, a is connected in series with the coil to compensate for temperature variations What kind of voltage is applied to the horizontal deflection plates of the oscilloscope? A small swamping resistance is connected in series with operating coil of a moving coil ammter in order to compensate for the effects of A procedure, or sequence of operations for determining whether a component or equipment is funcitoning or working normally. One of the basic functions of electronic circuit is A wheatstone bridge is balanced if A sensing element that provides a dc voltage less than 10mV with typical power range of 0.1 to 100mW What sensor provides a change of resistance with typical power range of 1uW to 10mW and with maximum frequency greater than 100GHz ammeter is used to measure high-frequency currents. What ammeter is mostly used in measuring high frequency currents? When the meter is unsufficiently damped, it is considered as This is a method of using a Wheatstone brdige to determine the distance from the test point to a fault in a telephone or telegraph line or cable. What do you call of the instrument used for measuring reactive power in VARS? For amplitude measurements, scale is calibrated in either volts per centimeter (V/cm), or millivolts per centimeter (mv/cm) When the vertical input is 0V, the electron beam may be position at the of the screen. The only use of voltage senstive meter movement sampling oscilloscope sawtooth sawtooth generator Schering Bridge sensitivity sensitivity signal generators sinusoidal slide-wire bridge Spectrum Analyzer spring action squared squared standard instrument/device storage oscilloscope stroboscope swamping resistors sweep voltage temperature variation Test the generation and manipulation of electronic waveshapes the ratio of resistors on one side of the bridge equals the ratio of resistors on the other side thermal converters thermistor sensor thermocouple thermocouple underdamped Varley Loop varmeter/reactive VA meter vertical vertical center very low voltage measurement

6 Type of power-line frequency meter composed of vibrating iron reed placed in alternating magnetic field Electrostatic instruments are exclusively used as Electrostatic instruments are exclusively used as Induction type instruments are mostly used as A dynamometer instrument is mainly used as a/an An electrodynamic meter used t measure power Dynamometers are mostly used as Which dynamometer type has uniform scale? What do you call of the frequency-sensitive bridge in which two adjacent arms are resistances and other are RC combinations? The two most common audio oscillators are When the capacitors of a Wein Bridge are replaced by inductors, the bridge becomes A dc bridge widely used for the accurate measurements of resistance Which of the following bridges measures dc resistance? When do you need a noise generator? has a series RC combination in one arm and a parallel RC combination in the adjoining arm and used as a notch filter in harmonic distortion analyzer. How much current does an electrostatic voltmeter require through it to operate? The forces that are acting on the pointer of an indicating instrument as it rest on its final deflected position. (damping torque is 0) Vibrating Reed Type voltmeters voltmeters watt-hour meter Wein Bridge Wein Bridge and Phase Shift Wein Inductance Bridge Wheatstone bridge Wheatstone bridge When evaluating noise characteristic of an amplifier wein bridge zero current