Advertisements
Advertisements
प्रश्न
An ac circuit consists of a series combination of circuit elements X and Y. The current is ahead of the voltage in phase by `pi /4` . If element X is a pure resistor of 100Ω ,
(a) name the circuit element Y.
(b) calculate the rms value of current, if rms value of voltage is 141V.
(c) what will happen if the ac source is replaced by a dc source ?
Advertisements
उत्तर
(a) Since current is leading voltage by `pi/4`, current leak in capacitive curcuit as X is pure resistor therefore Y capacitor.
(b) `phi = tan ^(-1) ((X_c - X_L)/R) X_L = 0`
`pi/4 = tan^(-1)((X_c)/R)`
`(X_c)/R= tan pi/4`
`(X_c)/R= 1` Xc = R
Xc = 100 Ω
`t = sqrt((100)^2 + (100)^2)`
`t = 100 sqrt(2) Omega = 100 xx 1.41 = 141 Omega `
`i_(RMS) = (e_(RMS))/z = 141/141 = 1A`
iRMS = 1A
(c) If we replace ac source by dc ω = 0
`X_c = 1/(omega _c)`
`X_c = 1/0 = ∞ Omega`
`i = e/z = 141/ ∞ `
i = 0
APPEARS IN
संबंधित प्रश्न
Three capacitors each of capacitance 9 pF are connected in series.
- What is the total capacitance of the combination?
- What is the potential difference across each capacitor if the combination is connected to a 120 V supply?
Deduce an expression for equivalent capacitance C when three capacitors C1, C2 and C3 connected in parallel.
The following figure shows two capacitors connected in series and joined to a battery. The graph shows the variation in potential as one moves from left to right on the branch containing the capacitors.
A parallel-plate capacitor having plate area 25 cm2 and separation 1⋅00 mm is connected to a battery of 6⋅0 V. Calculate the charge flown through the battery. How much work has been done by the battery during the process?
An ac circuit consists of a series combination of circuit elements X and Y. The current is ahead of the voltage in phase by `pi/4`. If element X is a pure resistor of 100 Ω,
(a) name the circuit element Y.
(b) calculate the rms value of current, if rms of voltage is 141 V.
(c) what will happen if the ac source is replaced by a dc source
Two parallel plate capacitors X and Y, have the same area of plates and same separation between plates. X has air and Y with dielectric of constant 2, between its plates. They are connected in series to a battery of 12 V. The ratio of electrostatic energy stored in X and Y is ______.
Three different capacitors are·connected in series. Then:-
Two charges q1 and q2 are placed at (0, 0, d) and (0, 0, – d) respectively. Find locus of points where the potential a zero.
