For given circuit the power factor is:

Important Questions on Alternating Current

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Beta Question Bank for Medical: Physics>Chapter 28 - Alternating Current>Exercise (Conceptual Questions)>Q 86

In a purely capacitive circuit, average power dissipated in the circuit is-

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Beta Question Bank for Medical: Physics>Chapter 28 - Alternating Current>Exercise (Previous Year Questions)>Q 1

The primary and secondary coil of a transformer have $50$ and $1500$turns respectively. If the magnetic flux $\varphi$ linked with the primary coil is given by $\varphi ={\varphi }_0+4t$ where $\varphi$ is in webers, $t$ is time in second, ${\varphi }_0$ is a constant, the output voltage across secondary coil is

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Beta Question Bank for Medical: Physics>Chapter 28 - Alternating Current>Exercise (Previous Year Questions)>Q 2

A transformer is used to light a $100 \mathrm{w}$ and $110 \mathrm{V}$ lamp from a $220 \mathrm{V}$ mains. If the main current is $0.5$ amp, the efficiency of the transformer is approximately -

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Beta Question Bank for Medical: Physics>Chapter 28 - Alternating Current>Exercise (Previous Year Questions)>Q 3

A transformer having efficiency of $90\%$ is working on $200 \mathrm{V}$ $3 \mathrm{kW}$ and power supply. If the current in the secondary coil is $6 \mathrm{A}$, the voltage across the secondary coil and the current in the primary coil respectively are 
 

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Beta Question Bank for Medical: Physics>Chapter 28 - Alternating Current>Exercise (Previous Year Questions)>Q 4

Energy loss in pure capacitance in A.C. circuit is:

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Beta Question Bank for Medical: Physics>Chapter 28 - Alternating Current>Exercise (Previous Year Questions)>Q 5

Power dissipated in pure inductance will be : 

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Beta Question Bank for Medical: Physics>Chapter 28 - Alternating Current>Exercise (Previous Year Questions)>Q 6

The power factor of L-R circuit is :

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Beta Question Bank for Medical: Physics>Chapter 28 - Alternating Current>Exercise (Previous Year Questions)>Q 7

If alternating current of rms value ’a’ flows through resistance R then power loss in resistance is :