Potentiometer is a 3 terminal device used to vary the resistance in any circuit. The galvanometer is first connected at point A and zero-deflection is observed at length PJ = 10 cm. MCQ on Measurement and Instrumentation for Electrical Engineering, 30 Most Asked Objective Questions or MCQ on Magnetism and Electromagnetism for Electrical Engineering, 17 Most Asked Objective Questions or MCQ on Network Theorems for Electrical Engineering, [TOP] Most Asked Objective Questions or MCQ on Transformer for Electrical Engineering. Trim pots are directly mounted onto circuit boards and can be set horizontally or vertically and can operate on a single or multi-turn basis. Damping of the Ballistic galvanometer is made small to, 42. The DC potentiometer method of measurement of resistance is used for measuring the unknown resistance of low value. Since these potentiometers work on the principle of resistance, they are also called as the resistive potentiometers. To measure a resistance with the help of a potentiometer it is, (a) necessary to standardise the potentiometer, (b) not necessary to standardise the potentiometer, (c) necessary to use a volt ratio box in conjunction with the potentiometer, 20. The pressure coil of a wattmeter should be connected on the supply side of the current coil when (a) load impedance is high, 12. Potentiometer is a primary sensor which converts the linear motion or the angular motion of a shaft into change in resistance. Presently the most common use I think would be as a component of a solid state motor speed control. E.m.f. In a single phase power factor meter the phase difference between the currents in the two pressure coils is, 31. So for better accuracy we can use potentiometer as the potentiometer does not draw any current from the circuit and hence gives an accurate value. Potentiometers, or pots, are a type of resistor used to control the output signal on an electronic device, like a guitar, amplifier, or speaker. An induction meter can handle current up to, 5. In a potentiometer wire experiment, the emf of a battery in the primary circuit is 2 0 V and its internal resistance is 5 Ω. This tutorial will explain how to measure resistance of the potentiometer through at digital multimeter for its accurate value. For handling greater currents induction wattmeters are used in conjunction with, 7. The Potentiometer is an electric instrument used to measure the EMF (electromotive force) of a given cell, the internal resistance of a cell. A multi-turn potentiometer may be used instead of the single-turn unit for greater adjustment precision, or the “precision potentiometer” circuit described in an earlier experiment may be used. As you can see in the image below, a shaft is attached with it to vary the resistance. The function of shunt in an ammeter is to, (b) increase the sensitivity of the ammeter, 11. For this device, only two are used (the middle one and one of the ends). The resistive element used in the construction of a potentiometer can be carbon composition, ceramic composition, metal film, conductive plastic or wirewound. If an instrument has cramped scale for larger values, then it follows, 44. Linear displacement . No explanation is available for this question! Andrew Daviel has covered this question quite well. 15.18. Q. Potentiometer is used for the measurement of. Since the reference voltage can be produced from an accurately calibrated voltage divider, a potentiometer can provide high precision in … According to application, instruments are classified as, 2. A potentiometer is an instrument for measuring voltage or 'potential difference' by comparison of an unknown voltage with a known reference voltage. ANSWER: Only (1) and (2) Answer & Explanation « Previous; Next » Related Content. A potentiometer is a variable resistor mechanically used to measure the difference of electrical potential between two electrical terminals. When a potentiometer is used as a rheostat, the “unused” terminal is often connected to the wiper terminal, like this: At first, this seems rather pointless, as it has no impact on resistance control. TE Connectivity (TE) manufactures various types of potentiometers including linear potentiometers, rotary sensors and encoders, and cable actuated position sensors called string pots. The actual reading may not be exactly what the potentiometer is rated for. Potentiometer techniques may also be used for current measurement, the unknown current being sent through a known resistance and the IR drop opposed by balancing it at the voltage terminals of the potentiometer. d. Only (1) and (2) e. All the above. This can be done by the comparing the unknown resistance with the standard resistance. The key difference between pH meter and potentiometer is that the pH meter measures the hydrogen ion activity in aqueous solutions, whereas the potentiometer measures the voltage by comparing an unknown voltage to a known voltage.. pH meter is often used in chemical analysis for the measurement of pH of water-based solutions. potentiometer is also called linear position sensors or resistors ruler and it is one of the most commonly used devise for measuring the displacement. The actual reading may not be exactly what the potentiometer is understood as shown in.., 21 B. measurement of low D.C. voltage flux-meter, ( b increase! Device to accurately “null” the measurement of resistance, they are also called as pots and it defined... And circuits measured by, 8 provides variable voltages while the Rheostat Thermostat! Increase the sensitivity of the two moving coils are at, 32 been by... 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