Electromagnetic...

What are the the dimensions of , where L, R, C and V have their usual meanings?

In an LCR series circuit, the potential difference between the terminals of the inductance is 60 V, that between the terminals of the capacitor is 30 V and that across the resistance is 40 V. Then, the supply voltage will be

In an oscillating LC circuit, the maximum charge on the capacitor is Q. The charge on the capacitor, when energy is stored equally between the electric and magnetic fields, is

A coil takes a current of 2 A and 200 W power from an alternating current source of 220 V, 50 Hz. What is the inductance of the coil?

A circular metal plate of radius 'R' is rotating with a uniform angular velocity 'ω' with its plane perpendicular to a uniform magnetic field B. Then, emf developed between the centre and the rim of the plate is

In an LR circuit, the reactance of the given inductor L is 40 , and the value of R is 30 . If in the circuit, an alternating emf of 200 V at 50 cycles/s is connected, the impedance of the circuit and the current will be

A short solenoid of length 4 cm, radius 2 cm and 100 turns is placed inside and on the axis of a long solenoid of length 80 cm and 1500 turns. A current of 3 A flows through the short solenoid. The mutual inductance of the two solenoids is

In a coil, if current changes from 10 A to 2 A in 0.1 s, the induced emf is 3.28 V. What is the self-inductance of the coil?

What is the capacitance of a capacitor whose reactance for AC frequency of 400 Hz is 25?

A 100 V AC source of frequency 500 Hz is connected to an LCR circuit with L = 8.1 mH, C = 12.5 µF and R = 10 (all are connected in series as shown in the figure). What is the quality factor of the circuit?

In an AC circuit, the voltage applied is E = E₀ sin ωt. The resulting current in the circuit is I = I₀ sin . The power consumption in the circuit is given by

If an alternating voltage is represented as E = 141 sin (628t), then what are the R.M.S. values of the voltage and the frequency?

If current of 30 A flowing in a primary coil is made zero in 0.1 sec, the emf induced in a secondary coil is 1.5 V. What is the mutual inductance between the coils?

The primary and secondary coils of a transformer have 50 and 1500 turns respectively. If the magnetic flux φ linked with the primary coil is given by φ = φ₀ + 4t (where φ is in weber, t (time) is in seconds and φ₀ is a constant), the output voltage across the secondary coil is

A transformer has an efficiency of 80%. It is connected to a power input of 5 kW at 200 V. If the secondary voltage is 250 V, what are the primary and secondary currents respectively?

A coil of resistance 100 and inductance 100 H is connected in series with 100 pF capacitor. What is the resonant frequency of the circuit?

The following series resonant LCR circuit has a quality factor (Q-factor) of 0.4 and a bandwidth of 1.3 kHz. What is the value of inductance?

The magnetic flux linked with a coil at any instant 't' given by another emf induced in the coil at t = 2s is

The value of mean induced e.m.f. in a coil is 8 volt. If the value of current in it varies from 2 amp to 4 amp in 0.05 second, what is self inductance of the coil?

In an LCR circuit, the capacitance is changed from C to 4C. For the same resonant frequency, what should be the inductance?

A coil of 40 H inductance is connected in series with a resistance of 8 and this combination is connected to the terminals of a 2 V battery. The inductive time constant (in seconds) of the circuit is

If a resistance of 100 , an inductance of 0.5 H and a capacitance of 10 x 10⁻⁶ F are connected in series with a 50 Hz AC supply, then what will be the impedance?

A coil of 1200 turns and mean area 500 cm² is held perpendicular to a uniform magnetic field of induction 4 × 10^-4 H. The resistance of the coil is 20 ohms. When the coil is rotated through 180° in the magnetic field in 0.1 s, what is the average electric current (in mA) induced?

In a transformer, the output current and voltage are 4A and 20 V respectively. If the ratio of number of turns in primary to secondary is 2 : 1, what are the input current and voltage?

The impedance of an AC circuit, which contains a capacitive reactance of 5 ohms and inductive reactance of 8 ohms, will be