| No. |
Question |
| 1 |
In an 8085 microprocessor, which one of the
following is the correct sequence of the machine cycles for the
execution of the DCR M instruction? |
| Options |
A) op-code fetch
|
B) op-code fetch, memory read, memory write |
C) op-code fetch memory read
|
D) op-code fetch memory write, memory write |
|
| Correct Answer |
B |
| |
| 2 |
equals |
| Options |
|
| Correct Answer |
D |
| |
| 3 |
Three DC currents I1, I2
and I3 meet at a node with I1entering and I2
and I3 leaving the node. I1 and I2 are
measured as 100mA and 99 mA with a � 1% accuracy. Then the value of I3
and the accuracy of I3 are |
| Options |
| A) 1 mA � 2% |
B) 199 mA � 2% |
| C) 1 mA � 2% |
D) 1 mA � 199% |
|
| Correct Answer |
C |
|
| 4 |
The input-output characteristic of a Schmidt
trigger has a hysteresis band of � 0.1 V. If the input voltage is 5 sin
(1000 pt), the delay between the
corresponding zero cross-over points of the output and input signals is |
| Options |
| A) 6.37 ms |
B) 0.02 ms
|
| C) 63.7 ms |
D) 2.0 ms |
|
| Correct Answer |
A |
| |
| 5 |
In a spirit level, 2.5mm of movement of the
bubble corresponds to a tilt angle of 25 seconds. The radius of
curvature of the tube of the spirit level is |
| Options |
| A) 52.1 m |
B) 34.4 m |
| C) 26.3 m |
D) 15.6 m |
|
| Correct Answer |
B |
| |
| 6 |
The loop transfer function of a system is given
by G(S)h(s) =
. The phase cross-over frequency is 5 rad/s. The value of the dead
time L is |
| Options |
| A) p/20 |
B) p/10 |
| C) -p/20 |
D) zero |
|
| Correct Answer |
B |
| |
| 7 |
An 8-bit microcontroller has an external RAM is
the memory map from 8000H to 9FFFH. The number of bytes this RAM can
store is |
| Options |
| A) 8193 |
B) 8191
|
| C) 8192 |
D) 8000 |
|
| Correct Answer |
C |
| |
| 8 |
Two copper-constantan thermocouples are connected
such that the two constantan wires are joined together. The two copper
wires are connected to the input of a low noise chopper stabilized
differential amplifier having a gain of 1000. One of the thermocouple
junctions is immersed in a flask containing ice and water in equal
proportion. The other thermocouple is at a temperature T. If the
output of the amplifier is 2.050V, the temperature T is |
| Options |
| A) 205�C |
B) 102.5�C |
| C) 51.25�C |
D) 50�C |
|
| Correct Answer |
D |
| |
| 9 |
The vectored address corresponding to the
software interrupt command RST7 in 8085 microprocessor is |
| Options |
| A) 0017H |
B) 0027H
|
| C) 0038H |
D) 0700H |
|
| Correct Answer |
C |
| |
| 10 |
For a first order instrument a 5% settling time
is equal to |
| Options |
| A) three times the time constant |
B) two times the time constant
|
C) the time constant
|
D) time required for the output signal to reaches 5%
of the final value |
|
| Correct Answer |
A |
| |
| 11 |
The measurements of a source voltage are 5.9V,
5.7V and 6.1V. The sample standard deviation of the readings is |
| Options |
| A) 0.013 |
B) 0.04 |
| C) 0.115 |
D) 0.2 |
|
| Correct Answer |
D |
| |
| 12 |
In an INTEL 8085 microprocessor the ADDRESS-DATA
bus and the DATA bus are |
| Options |
| A) Non multiplexed |
B) Multiplexed |
| C) Duplicated |
D) Same as CONTROL bus |
|
| Correct Answer |
B |
| |
| 13 |
The number of comparators required in an 8-bit
flash-type AID converter is |
| Options |
| A) 256 |
B) 255
|
| C) (8 + 2) |
D) 8 |
|
| Correct Answer |
B |
| |
| 14 |
An ultrasonic beam of frequency 1 MHz and
intensity 0.5 W/cm2 passes through a layer of soft tissue of
thickness t with an attenuation coefficient of 1.18cm-1. The
ratio of output to input power is 1/e2. The thickness of the
tissue is |
| Options |
| A) 1 cm |
B) 1.695 cm |
| C) 2.408 cm |
D) 3.712 cm |
|
| Correct Answer |
B |
| |
| 15 |
A twisted pair of wires is used for connecting
the signal source with the instrumentation amplifier, as it helps
reducing |
| Options |
| A) the effect of external interference |
B) the error due to bias currents in the amplifier |
| C) the loading of the source by the amplifier |
D) the common mode voltage |
|
| Correct Answer |
C |
| |
| 16 |
The output from a 633 nm He-Ne laser comes out
from the mirror with a beam diameter of lmm and diverges to the far
field. It is brought to a focus by a convex lens of focal length of 17
mm. The spot size diameter of the beam at the focal point is |
| Options |
| A) 20 m m |
B) 26 m m
|
| C) 52 m m |
D) 13 m m |
|
| Correct Answer |
C |
| |
| 17 |
International temperature scale in the range
0-630oC is defined by means of a |
| Options |
| A) mercury pressure spring thermometer |
B) platinum-platinum. 10% rhodium thermocouple |
| C) platinum resistance thermometer |
D) total radiation pyrometer. |
|
| Correct Answer |
D |
| |
| 18 |
A microprocessor has an instruction XOR (r1 ,
r2) which performs an Exclusive OR operation of registers r1,r2
and stores the result in r1. After the following instructions
are executed
XOR (r2, r1)XOR (r1,r2)
XOR (r2,r1)
Which one of the following is true? |
| Options |
A) Content of register r1 is half sum of r1
and r2
|
B) Content of register r2 is half sum of r1
and r2
|
| C) Contents of registers r1 and r2
remain unaltered |
D) Contents of registers r1 and r2
are swapped
|
|
| Correct Answer |
D |
| |
| 19 |
A second order feedback system is found to be
oscillating with a high frequency. The oscillations |
| Options |
| A) can be reduced by increasing the proportional
action |
B) can be reduced by increasing the integral action |
| C) can be reduced by increasing the derivative action |
D) cannot be reduced |
|
| Correct Answer |
B |
| |
| 20 |
For a suppressed carrier amplitude modulator
(AM-SC) system, the carrier and the modulating inputs are xc
(t) = cos wc t and xm
(t) = 0.5 sin wm t, respectively.
The output of the system is proportional to |
| Options |
| A) sin (wc +
wm) t � sin (wc
- wm) t |
B) sin (wc +
wm) t + cos (wc
-wm) t |
| C) (1 + 0.5 sin wm
t) cos wc t |
D) (1- 0.5 sin wm
t) cos wc t |
|
| Correct Answer |
B |
