Question) The A.C. voltage and the current in an L-C-R A.C. series circuit are given by the following expression. V=2002 cos 300t-55° V, 1=102 cos 3000t-10°A. Calculate the impedance and the resistance (R) of the above circuit.
Q. The value of a uniform magnetic field drops to zero from 2 T in 0.01 sec only. Determine the current induced in a circular coil ( of radius 3 cm and of 50 turns ) placed in a plane perpendicular to that magnetic field. [Resistance of the coil is 30 . What is the relation of electrical susceptibility and magnetic permeability with the velocity of light ? Give the range of wave length in Å, of visible light wave.
17. Define the peak and r.m.s. value of an alternating current and establish relation between them.
Equation of an alternating e.m.f. is given : e=200 sin(1000t) volt. Find r.m.s. value of its potential and frequency.
Q. The resistance of a coil is 10 and number of turns is 1000. The magnetic flux linked with the coil at a moment is 5.5 Wb. After 0.1 sec the magnetic flux reduced to to 0.5 Wb. Then (i) Find electromotive force and (ii) what is the value of flowing charge?
Q. A galvanometer of resistance 45 ohm, shunted with a resistance of 5 ohm is joined in series with a resistance of 84 ohm and a battery of e.m.f. 4.5 volt having internal resistance 1.5ohm. Find the current passing through (a) the battery, (b) the galvanometer, and (c) the shunt.
Q(b). Calculate the steady state current in the 2 ohm resistor.
Shown in the circuit in the figure. The internal resistance of the battery is negligible and the capacitance of the condenser C is 0.2 microfarad.
Two batteries of emfs 5 V and 10 V, their internal resistances are 0.1 and O.5
respectively. They are joined oppositely in series and then connected with a 10
external resistance. What will be the current in the circuit ?
Question) The A.C. voltage and the current in an L-C-R A.C. series circuit are given by the following expression. Calculate the impedance and the resistance (R) of the above circuit.
Q. An inductor of 0.50 H and a resistance of 100 Ohm are connected in a series with an A.C. source = 240 volt and 50 Hz. Find
(1) the maximum current in the inductor and
(2) the phase difference and the time lag between the current and the voltage.
(Ans. (1) 1.82 A (2) 57.5 and 3.2 ms)
(A) What is the source frequency for which current amplitude is maximum ?
(B) Calculate the quality factor for the circuit.
(C) For which frequencies of the source is the power transferred to he current half the power at the resonance frequencies ?
(D) What is the current amplitude at these frequency ?
(E) Obtain maximum power developed in circuit.