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**Description :** When an alternating current passes through an ohmic resistance the electrical power converted into heat is?

**Last Answer :** When an alternating current passes through an ohmic resistance the electrical power converted into heat is true power.

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**Description :** A 200 V dc shunt motor is running at 1000 rpm and drawing a current of 10 A. Its armature winding resistance is 2 Ohm. It. is braked by plugging. The resistance to be connected in series with armature to restrict armature current to 10 A, is

**Last Answer :** A 200 V dc shunt motor is running at 1000 rpm and drawing a current of 10 A. Its armature winding resistance is 2 Ohm. It. is braked by plugging. The resistance to be connected in series with armature to restrict armature current to 10 A, is 36 Ohm

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**Description :** Why does the speed of a DC shunt motor decrease as the load increases?

**Last Answer :** Because if the load is increasing then the torque must also be increase. If not then the speed of motor will decrease.

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**Description :** Transmission efficiency of a transmission line increases with the

**Last Answer :** Transmission efficiency of a transmission line increases with the increase in power factor and voltage

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**Description :** What happens to the resistance of a wire when its length as well as the cross-sectional area are doubled? A) It doubles B) It becomes 4 times C) It becomes 2π times D) It remains the same

**Last Answer :** Automatically the resistivity will increase as they are the factors affecting the resistivity

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**Description :** A sine wave voltage is applied across an inductor. When the frequency of the voltage is decreased, the current decreases.

**Last Answer :** The question seems to be wrong. Increase in frequency would actually decrease the current through the Inductor. This happens because inductive reactance Xl is directly proportional to frequency. And if frequency increases the value of Xl would ... vice versa. Xl= 2*pi*f*L I=E/Z Z=sqrt(R^2+Xl^2)

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**Description :** What happens when a current flows through a wire?

**Last Answer :** Current can produce two effect one is heating effect and second is magnetic effect.

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**Description :** What happens when you reverse the direction of the current in an electromagnet?

**Last Answer :** When you reverse current direction in an electromagnet, the magnetic poles will also change.

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**Description :** State the procedure for testing of earth pit resistance with necessary diagrams.

**Last Answer :** Following procedure (Method) for testing of earth pit resistance with necessary diagrams. 1) Earth Tester : i) Three point method ii) Four point method 2) By Potential drop method 3 ... of that earthing pit. In this test the accuracy is less but electrical rods are not required.

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**Description :** what is equivalent resistance when four 4 Ohm resistors are connected in i) series ii) parallel

**Last Answer :** equivalent resistance

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**Description :** Define resistance with its unit.

**Last Answer :** Resistance is a measure of the degree to which a substance impedes the flow of electric current induced by a voltage. Or Resistance is the opposition to current flow in an electrical circuit. Unit is ohm.(Ω)

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**Description :** What is the mathematical relationship between resistance and conductance?

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**Description :** How does the resistance of a conductor compare to that of an insulator?

**Last Answer :** The resistance of a conductor can be significantly lower than the resistance of an insulator, depending on each material's atomic properties.

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**Description :** Parallel Reactance and Resistance Example 1

**Last Answer :** Parallel Reactance and Resistance Example 1

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**Description :** AC Circuits with Resistance but No Reactance

**Last Answer :** AC Circuits with Resistance but No Reactance AC Circuits with Resistance but No Reactance Series resistances let two resistances R 1 and R 2 are connected in series as shows in figure and there ... voltage. Voltage V A is common to both the branch hence voltage V A is common reference.

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**Description :** Problems on resistance and resistivity

**Last Answer :** Problem on resistance and resistivity 1 : https://youtu.be/OqavD7OlZUs Problem on resistance and resistivity 2 : https://youtu.be/0eo8VO8cpwk Problem on resistance and resistivity 3 : https:// ... https://youtu.be/3neLRCTz0RQ Problem on resistance and resistivity 13 : https://youtu.be/vBCkvPOiztY

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**Description :** Problem on temperature coefficient of resistance 3

**Last Answer :** Problem on temperature coefficient of resistance 3

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**Description :** Problem on temperature coefficient of resistance 2

**Last Answer :** Problem on temperature coefficient of resistance 2

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**Description :** Problem on temperature coefficient of resistance 1

**Last Answer :** Problem on temperature coefficient of resistance 1

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**Description :** Problem on resistance and resistivity 13

**Last Answer :** Problem on resistance and resistivity 13

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**Description :** Problem on resistance and resistivity 12

**Last Answer :** Problem on resistance and resistivity 12

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**Description :** Problem on resistance and resistivity 11

**Last Answer :** Problem on resistance and resistivity 11

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**Description :** Problem on resistance and resistivity 10

**Last Answer :** Problem on resistance and resistivity 10

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**Description :** Problem on resistance and resistivity 9

**Last Answer :** Problem on resistance and resistivity 9

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**Description :** Problem on resistance and resistivity 8

**Last Answer :** Problem on resistance and resistivity 8

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**Description :** Problem on resistance and resistivity 7

**Last Answer :** Problem on resistance and resistivity 7

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**Description :** Problem on resistance and resistivity 6

**Last Answer :** Problem on resistance and resistivity 6

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**Description :** Problem on resistance and resistivity 5

**Last Answer :** Problem on resistance and resistivity 5

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**Description :** Problem on resistance and resistivity 4

**Last Answer :** Problem on resistance and resistivity 4

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**Description :** Problem on resistance and resistivity 3

**Last Answer :** Problem on resistance and resistivity 3

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**Description :** Problem on resistance and resistivity 2

**Last Answer :** Problem on resistance and resistivity 2

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**Description :** Problem on resistance and resistivity 1

**Last Answer :** Problem on resistance and resistivity 1

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**Description :** Name two methods for measurement of low, medium and high resistance. Give one advantage and one limitation of V- I method.

**Last Answer :** Methods for measurement of low resistance: 1. Ammeter voltmeter method 2. Kelvin's bridge method 3. Ohm meter method 4. Potentiometer method 5. Digital/analog multi-meter ... must be infinity for perfectly accurate measurement which is not possible. 2. Connection errors.

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**Description :** Name the method used to measure following resistances:- (i) Low resistance (ii) Medium resistance (iii) Insulation resistance (iv) Earth resistance.

**Last Answer :** Following are the methods used to measure resistances:- (i) Low resistance: 1.Voltmeter-Ammeter Method 2. Kelvin's Double bridge Method (ii) Medium resistance: 1.Voltmeter-Ammeter Method 2. ... of Charge Method (iv) Earth resistance : 1. Fall of Potential Method 2. Earth tester

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**Description :** Write any two factors on which earth resistance depends.

**Last Answer :** Factors on which earth resistance depends: (1) The shape and material used for the electrode (2) Depth of the electrode in the ground. (3) The specific resistance of the soil around the electrode (4) Moisture content in the soil. (5) Nature of soil

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**Description :** State the use of shunt and series resistance used in extension of meter.

**Last Answer :** Use of shunt and series resistance: i) Use of shunt: To extend the range of Ammeter. ii) Use of series resistance: To extend the range of Voltmeter.

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**Description :** State the range for low and medium resistance.

**Last Answer :** Low resistances: less than 1 ohm. Medium resistances: 1 ohm to 0.1 Mega ohm.

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**Description :** Explain V- I method of measurement of medium resistance.

**Last Answer :** In this method, use suitable source, ammeter and voltmeter and connect them as shown in the above diagram. Take reading of voltmeter and ammeter, then value of resistance = R = V/I Ω To minimise the error take 4 to 5 observation for the same resistance and take their average.

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**Description :** Give classification of resistance based on their ranges.

**Last Answer :** Classification of Resistances Based on Their Ranges: 1) Low resistance: less than 1 ohm. 2) Medium resistance: 1 ohm to 0.1 Mega ohms. 3) High resistance: greater than 0.1 Mega ohms.

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**Description :** Define pinch off voltage and drain resistance of FET.

**Last Answer :** 1 . Pinch-off Voltage: It is the value of the drain to source voltage VDS at which the drain current ID reaches its constant saturation value. Any further increase in VDS does not have any ... drain to source voltage to the change in drain current. It is also called AC/dynamic drain resistance.

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**Description :** Define the following terms as referred to battery. a) E.M.F b) Internal resistance c) Ah efficiency d) WAh efficiency

**Last Answer :** a) E.M.F : The electromotive force of a battery is defined as the energy spent or the work done in taking a unit positive charge around the complete circuit of the battery i.e., in ... input required to restore the initial state of charge, under specified conditions, is called Watt-hr efficiency.

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**Description :** A resistor in which the resistance changes exponentially with change in temperature is called as A) Potentiometer B) Phototransistor C) Varactor D) Thermistor

**Last Answer :** A resistor in which the resistance changes exponentially with change in temperature is called as Thermistor

156 views

**Description :** We connected a 35V dc supply to a resistance of 600 Ohm in series with an unknown resistance R.A. voltmeter having a resistance of 1.2 kOhm is connected across 600 Ohm resistance and read 5v. The value of resistance R will be

**Last Answer :** We connected a 35V dc supply to a resistance of 600 Ohm in series with an unknown resistance R.A. voltmeter having a resistance of 1.2 kOhm is connected across 600 Ohm resistance and read 5v. The value of resistance R will be 2.4 kOhm

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**Description :** Which of the following is the name given to resistance of thin films that are uniform in thickness? A) Area resistance B) Sheet resistance C) Filmy resistance D) None of these

**Last Answer :** Which of the following is the name given to resistance of thin films that are uniform in thickness? A) Area resistance B) Sheet resistance C) Filmy resistance D) None of these

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**Description :** What is the resistance of a coil which draws 10 A and dissipates 1520 W? A) 152 Ω B) 15.2 Ω C) 1.52 Ω D) None of these

**Last Answer :** What is the resistance of a coil which draws 10 A and dissipates 1520 W? A) 152 Ω B) 15.2 Ω C) 1.52 Ω D) None of these

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**Description :** Consider a cube of material of sides 1 cm with a resistance of 0.003 Ω between its opposite faces. What is the resistance if the same volume of the material is drawn into a length of 50 cm with a uniform cross – section? A) 0.003 Ω B) 0.15 Ω C) 7.5 Ω D) None of these

**Last Answer :** Consider a cube of material of sides 1 cm with a resistance of 0.003 Ω between its opposite faces. What is the resistance if the same volume of the material is drawn into a length of 50 cm with a uniform cross – section? A) 0.003 Ω B) 0.15 Ω C) 7.5 Ω D) None of these

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**Description :** What is the resistance of a 160 m wire with a uniform diameter of 0.28 mm, if the specific resistance is 12.32 μΩ-cm? A) 3.2 Ω B) 3.2 μΩ C) 0.8 Ω D) None of these

**Last Answer :** What is the resistance of a 160 m wire with a uniform diameter of 0.28 mm, if the specific resistance is 12.32 μΩ-cm? A) 3.2 Ω B) 3.2 μΩ C) 0.8 Ω D) None of these

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**Description :** What is the total resistance if 5 resistors of 20 Ω each are connected in series? A) 100 Ω B) 4 Ω C) 20 Ω D) None of these

**Last Answer :** What is the total resistance if 5 resistors of 20 Ω each are connected in series? A) 100 Ω B) 4 Ω C) 20 Ω D) None of these

239 views

**Description :** When both the inductance and resistance of a coil are doubled the value of?

**Last Answer :** When both the inductance and resistance of a coil are doubled the value of time constant remains unchanged.

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