Alternating Cur...

The power factor of an AC circuit having resistance R and inductance L (connected in series) and an angular velocity ω is

An installation consisting of an electric motor driving a water pump left 75 L of water per sec of a height of 4.7 m. If the motor consumes a power of 5 kW, then the efficiency of the installation is

An ideal transformer has 500 and 5000 turn in primary and secondary windings respectively. If the primary voltage is connected to a 6 V battery, then the secondary voltage is

A resistor and a capacitor are connected in series with an AC source. If the potential drop across the capacitor is 5 V, and that across resistor is 12 V, then applied voltage is

An ideal coil of 10 H is connected in series with a resistance of 5 Ω and a battery of 5 V. 2 s after the connection is made, the current flowing (in ampere) in the circuit is

A coil of inductance 300 mH and resistance 2 Ω is connected to a source of voltage 2V. The current reaches half of its steady state value in

A 4µF capacitor, a resistance of 2.5 m Ωis in series with 12 V battery. Find the time after which the potential difference across the capacitor is 3 times the potential difference across the resistor. (given, ln (2) = 0.693)

A coil is wound on an iron core and looped back on itself so that core has two sets of closely wound coils carrying currents in opposite directions. The self-inductance is

A movable wire is moved to the right causing an anticlock-wise induced current Fig. The direction of magnetic induction in the region P points

In the circuit shown in Fig, the bulb B will become suddenly bright when