PDC Unit-I
JNTUH previous bits
SECTION-I:
CHOOSE THE CORRECT ANSWERS
1. The lower cutoff
frequency of a low pass RC circuit is [ ]
( a ) 0 ( b ) 2πRC ( c ) 1/2πRC ( d )
infinity
2.The transmission
error at the end of the ramp input is defined as [ ]
( a ) (output-input)/output ( b )
(output-input)/input ( c )(input-output)/output
( d ) (input-output)/output
3. For double
differentiation, two high –pass networks are connected in cascade with time
constants of [ ]
( a ) first one is
small and second is large ( b ) first one is large and next is small
( c ) both are small ( d ) both are
large
4. What is the response of step
input to a high pass RC circuit [ ]
a) V e-t/RC b)
V (1- et/RC)
c) V et/RC
d) V(1- e-t/RC )
5. When RC high pass circuit
act as a differentiator? [ ]
a)
RC<<T b) RC>>T c)RC=T d)RC=0
6. What is the name of the
circuit which converts square wave in to spikes [ ]
a) Low pass
RC b) Bi stable multi c) High pass RC d) Monoshot
7.The waveform which preserves
its form when transmitted through a linear network is a
___________. [ ]
(a) Sine
wave (b) Step signal (c) impulse signal (d) ramp signal
8. An RC high pass circuit has
R= 1kΩ and C=0.5 μF. Its lower cutoff frequency is [ ]
(a) zero (b)
318.3 Hz (c) 1kHz (d) infinity
9. For a integrator, if input
is square wave then the output waveform is _____ [ ]
(a) Impulse
(b) Sawtooth wave (c) Triangular wave (d) Both a and c
10. Gain of integrator ________
with frequency. [ ]
(a) decreases
(b) increases (c) both a and b (d) no change
11. A ringing circuit has a
quality factor Q=24. This circuit will ring for how many number of cycles? [ ]
(a) 24 (b)
12 (c) 8 (d) 6
12. The rise time of the output
of a low pass RC circuit is given by [ ]
(a) 2.2 RC (b) 0.35/fH (c)
2.2τ (d) all the above
Section-II
Fill
in the blanks
13. High-pass circuit is treated as a
differentiator, if the phase shift between the input and output is at least
___________
14.
The condition for perfect compensation of an attenuator is ________
15. For DC input signal capacitor C acts
as a ___________
16. The average value of the
output value of an RC high pass circuit is _________
17. In RC
integrator circuit the output is taken across --------
18. The
current flowing through the capacitor when the voltage across the capacitor is
V __________
19. The
output voltage Vo of RC differentiator for input Vi is ____________
20.
_____________ is the condition for an RC high pass circuit to acts as a
differentiator.
21. Time
constant of RL circuit is ____________.
22. Rise
time of a Low pass filter is ________________________.
23. The process of converting
pulses into spikes is called _____________.
24.. Write
the relationship between time constant and tilt?
Prepared by
G.Swathi &C.Swathi