MCQ
When an ac source of $e.m.f$. $e = {E_0}$$\sin (100\,t)$ is connected across a circuit, the phase difference between the $e.m.f$. $e$ and the current $i$ in the circuit is observed to be $\pi /4$, as shown in the diagram. If the circuit consists possibly only of $RC$ or $LC$ in series, find the relationship between the two elements
  • $R = 1k\Omega ,\,C = 10\mu F$
  • B
    $R = 1k\Omega ,\,C = 1\mu F$
  • C
    $R = 1k\Omega ,\,L = 10H$
  • D
    $R = 1k\Omega ,\,L = 1H$

Answer

Correct option: A.
$R = 1k\Omega ,\,C = 10\mu F$
a
(a) As the current i leads the voltage by $\frac{\pi }{4},$ it is an $RC$ circuit, hence $\tan \phi = \frac{{{X_C}}}{R}$==> $\tan \frac{\pi }{4} = \frac{1}{{\omega \,CR}}$
==> $\omega \,CR = 1$ as $\omega$ $= 100 \,rad/sec$
==> $CR = \frac{1}{{100}}se{c^{ - 1}}$.
From all the given options only option $(a)$ is correct.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

A thin spherical insulating shell of radius $R$ carries a uniformly distributed charge such that the potential at its surface is $V _0$. A hole with a small area $\alpha 4 \pi R ^2(\alpha<<1)$ is made on the shell without affecting the rest of the shell. Which one of the following statements is correct?
Consider the following two statements A and B, and identify the correct choice out of given answers
A. Thermo e.m.f. is minimum at neutral temperature of a thermocouple
B. When two junctions made of two different metallic wires are maintained at different temperatures, an electric current is generated in the circuit.
A $n-p-n$ transistor is connected in commonemitter configuration in which collector supply is $8\, V$ and the voltage drop across the load resistance of $800\,\Omega $ connected in the collector circuit is $0.8\, V$. If the current amplication factor $\alpha $ is $25/26$, the collector-emitter voltage $V_{CE}$ and the base current $I_B$ will be
Which of the following is not a correct statement
The order of the size of nucleus and Bohr radius of an atom respectively are
Two wires of equal diameters, of resistivities $\rho_1$ and $\rho_2$ and lengths $l_1$ and $l_2$, respectively, are joined in series. The equivalent resistivity of the combination is
Which of the following is true for photon
In a transistor the base is very lightly doped as compared to the emitter because by doing so
$A$ semicircle conducting ring of radius $R$ is placed in the $xy$ plane, as shown in the figure. $A$ uniform magnetic field is set up along the $x$ -axis. No $emf$, will be induced in the ring. if
Binding energy of a nucleus is