An ideal transformer steps up an input voltage of 22 V to an output voltage of 220 V. If it operates a device having a load resistance of 110 Ω, the current drawn by the primary coil is:

The peak value of an alternating current is 5 A and frequency is 60 Hz. How long will the current, starting from zero, take to reach the peak value?

An AC circuit contains a resistance of 1 kΩ, a capacitor of 0.1 μF, and an inductor of 1 mH connected in series. The resonance frequency of the circuit is approximately: