Advertisements
Advertisements
प्रश्न
An ideal inductor is connected across an AC source of voltage. The current in the circuit ______.
विकल्प
is ahead of the voltage in phase by π.
lags voltage in phase by π.
is ahead of voltage in phase by `pi"/"2`.
lags voltage in phase by `pi"/"2`.
Advertisements
उत्तर
An ideal inductor is connected across an AC source of voltage. The current in the circuit `underlinebb("lags voltage in phase by "pi"/"2)`.
Explanation:
`epsi = (-LdI)/(dt)`
`epsi_0 sinomegat = (-LdI)/(dt)`
In magnitude `(dI)/(dt) = epsi_0/L sinomegat`
On integrating both sides,
I = `intepsi_0/L sinomegat dt`
I = `epsi_0/L ((-1)/omega cosomegat)`
I = `-epsi_0/(Lomega) (cos omegat)`
I = `-epsi_0/(Lomega) sin(pi/2 - omegat)`
= `epsi_0/(Lomega) sin(omegat - pi/2)`
I = `I_0 sin(omegat - pi/2)`
Hence, current lags voltage in phase π/2.
APPEARS IN
संबंधित प्रश्न
An inductor, a resistance and a capacitor are joined in series with an AC source. As the frequency of the source is slightly increased from a very low value, the reactance
An inductor coil of some resistance is connected to an AC source. Which of the following quantities have zero average value over a cycle?
(a) Current
(b) Induced emf in the inductor
(c) Joule heat
(d) Magnetic energy stored in the inductor
An inductor-coil, a capacitor and an AC source of rms voltage 24 V are connected in series. When the frequency of the source is varied, a maximum rms current of 6.0 A is observed. If this inductor coil is connected to a battery of emf 12 V and internal resistance 4.0 Ω, what will be the current?
Obtain if the circuit is connected to a high-frequency supply (240 V, 10 kHz). Hence, explain the statement that at very high frequency, an inductor in a circuit nearly amounts to an open circuit. How does an inductor behave in a dc circuit after the steady state?
An applied voltage signal consists of a superposition of a dc voltage and an ac voltage of high frequency. The circuit consists of an inductor and a capacitor in series. Show that the dc signal will appear across C and the ac signal across L.
Average power supplied to an inductor over one complete cycle is ______.
If circuit containing inductance only, the current ______.
An electrical device draws 2kW power from AC mains (voltage 223V (rms) = `sqrt(50,000)` V). The current differs (lags) in phase by `phi(tan phi = (-3)/4)` as compared to voltage. Find (i) R, (ii) XC – XL, and (iii) IM. Another device has twice the values for R, XC and XL. How are the answers affected?
