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It is required to measure the true open circuit e.m.f. of a battery. The best device is D.C. potentiometer.

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Draw the circuit diagram of battery charger using SCR and explain it’s working.

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Describe the difference between an open circuit and a short circuit.

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Open circuit means the wire is cut meaning power will not flow and close circuit means wire is not cut and hence power will flow.Short circuit is the same as close circuit

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A d.c. source has an open circuit voltage of 30 V and an internal resistance of 1.5 Ohm. A resistive load is connected to the source. Maximum power dissipated in the load is (A) 300 W (B) 150 W (C) 45 W (D) 20 W

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A d.c. source has an open circuit voltage of 30 V and an internal resistance of 1.5 Ohm. A resistive load is connected to the source. Maximum power dissipated in the load is 150 W

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open emitter BJT drive circuit:

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An open-circuit test on a transformer is conducted primarily to measure?

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The open-circuit test in a transformer is used to measure

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The counter e.m.f. of a d.c. motor helps in energy conversion.

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When the armature of a D.C. motor rotates, e.m.f. induced is back e.m.f.

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If B is the flux density, I the length of conductor and v the velocity of conductor, then induced e.m.f. is given by Blv.

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In case of D.C. shunt motors the speed is dependent on back e.m.f. only because flux is practically constant in D:C. shunt motors.

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A Pyrheliometer is an instrument to measure : intensity of direct solar radiation at normal incidence 

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Voltmeter is used to measure voltage.

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A battery is known to have an EMF of 5.0V but when a certain voltmeter is connected to it the reading is 4.9V. The battery can deliver a current of 0.40A when connected to a resistance of 12ohms. What is the resistance of the voltmeter?

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Integrating instruments are those which measure the total quantity of electricity delivered in a particular time.

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What is the unit of measure for voltage?

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Voltage measured in volts.

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Yes it can...

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Voltmeter is used to measure voltage in a circuit.Ohmmeter is used to measure the resistance of a component in a circuit.

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