MCQ
An oscillator is nothing but an amplifier with
  • Positive feed back
  • B
    Large gain
  • C
    No feedback
  • D
    Negative feedback

Answer

Correct option: A.
Positive feed back
a
(a)In oscillator, a portion of the output power is returned back $(feed \,\,back)$  to the input in phase with the starting power. This process is termed as positive feedback.

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 satellite is orbiting just above the surface of the earth with period T. If $\frac{x}{2}$ is the density of the earth and $G$ is the universal constant of gravitation, the quantity $\frac{3 \pi}{2 G x}$ represents:
An ac circuit consists of an inductor of inductance $0.5 \,H $ and a capacitor of capacitance $8$ $\mu$ $F$ in series. The current in the circuit is maximum when the angular frequency of ac source is
A thin metallic spherical shell contains a charge $Q$ on it. A point charge $+q$ is placed at the centre of the shell and another charge $q'$ is placed outside it as shown in fig. All  the three charges are positive. The force on the central charge due to the shell is :-
A bead of mass $\frac {1}{2}\,kg$ starts from rest from $A$ to move in a vertical plane along a smooth fixed quarter ring of radius $5\,m$, under the action of a constant horizontal force $F = 5\,N$ as shown. The speed of bead as it reaches the point $B$ is ................ $\mathrm{m}/ \mathrm{s}$ [Take $g = 10\,m/s^2$ ]
Energy generation in stars is mainly due to
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
A resonant $ ac $ circuit contains a capacitor of capacitance ${10^{ - 6}}F$ and an inductor of ${10^{ - 4}}H.$ The frequency of electrical oscillations will be
A ball is thrown vertically upwards from the top of a tower with a velocity $u$. This ball  reaches the ground level with a velocity $4\,u$. The height of the tower is 
In young's double slit experiment, the fringe width is $12\,mm$. If the entire arrangement is placed in water of refractive index $\frac{4}{3}$, then the fringe width becomes $(in\,mm)$
In a series $LCR$ circuit, the inductive reactance $\left( X _{ L }\right)$ is $10\, \Omega$ and the capacitive reactance $\left( X _{ C }\right)$ is $4\, \Omega$. The resistance $( R )$ in the circuit is $6\, \Omega$. The power factor of the circuit is :