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The ratio of secondary to the primary turns in a transformer is 3 : 2. If the power output be P, then the input power neglecting all losses must be equal

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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A transformer with turns ratio `N_1/N_2=50/1` is connected to a `120 V' 'AC` supply. If primary and secondary circuit resistances are `1.5 kOmega and 1Omega` respectively, then find out power of

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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When the frequency of an AC circuit is doubled, then the capacitive reactance will b e

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In an L-C-R series circuit, the voltage across each of the components L, C and R is 100 V. The voltage across the LC combination will

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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In an L-C-R circuit, capacitance is changed from C to 2C. For the resonant frequency to remain unchanged, the inductance should be changed from `L` to

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Which of the following statements(s) is/are incorrect with respect to tuning

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Which of the following statements is/are incorrect about

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In an AC series L-C-R circuit, applied voltage is `V= {100sqrt2 sin (omegat + 45°)} V` Given that, `R - 30 Omega, X_L = 50 Omega and X_c = 10 Omega.` Now match the following two columns. Column I Column II A. Current in the circuit p. 120 SI units B. Power dissipated in the circuit q. 60 SI units C. Potential difference across resistance r. 2 SI units D. Potential difference across inductance s. None

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Match the Column I (AC circuit condition) with Column II (power dissipation) and select the correct answer from the codes given below. Column I Column II A. Resistive circuit p. No power dissipation B. Purely inductive or capacitive circuit q. Maximum power dissipation because of `X_C=X_L` C. L-C -R series circuit r. Power dissipated only in the resistor D. Power dissipated at resonance in L-C -R circuit s. Maximum power dissipation

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Assertion: Average value of current in half the cycle of an AC circuit cannot be zero. Reason: For positive half cycle average value of current is `(i_0)/pi`, where `i_0` is the peak value

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Assertion: The alternating current lags behind the emf by a phase angle of `pi'/'2`, when AC flows through an inductor. Reason: The inductive reactance increases as the frequency of AC source

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Assertion: Inductive reactance of an inductor in DC circuit is zero. Reason: Angular frequency of DC circuit is

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Assertion: If an inductor coil is connected to DC source, the current supplied by it is `I_1`.If the same coil is connected with an AC source of same voltage. Then, current is `I_2`. Then, `I_2 < I_1.` Reason: In AC circuit, inductor coil offers more

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Assertion: When the capacitor is connected to an AC source, it limits or regulates the current, but does not completely prevent the flow of charge. Reason: The capacitor is alternately charged and discharged as the current reverses each

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Assertion: Capacitor serves as a barrier for DC and offers an easy path to AC. Reason: Capacitive reactance is directly proportional to

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Assertion: In series, L-C-R circuit, voltage across capacitor is always less than the applied voltage. Reason: In series L-C-R circuit,

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Assertion: `X_C < X_L, phi` is positive and the circuit is predominantly capacitive. The current in the circuit leads the source voltage. Reason: If `X_C < X_L, phi` is negative and the circuit is predominantly inductive. The current in the circuit lags the source

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Assertion: Resonance phenomenon is exhibited by a circuit only, if both L and C are present in the circuit.Reason: Voltage across L & C does not cancel each other and the current amplitude is `V_m'/' R`, the total source voltage appearing across R causes

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Assertion: Average power in an AC circuit is given by `P=I_(rms)^2 R` . Reason: In one full cycle, net power is dissipated not only in a

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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Assertion: At resonance, power of L-C-R series circuit is zero. Reason: At resonance, `X_C >

asked Mar 20, 2022 in 12th Physics by varun (6.7k points)

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