2. b it the beez practice 0
DESCRIPTION
questionsTRANSCRIPT
EASY
EASYMATHEMATICS
He was known as the father of modern geometry
EASY
ANSWER
Euclid
EASYEST
a flat conductor separated by an insulating dielectric from a large ground plane that is usually one-quarter or one-half wavelength long
EASY
ANSWER
microstrip
EASYEST
One complete revolution around a Smith Chart represents _________ wavelengths.
EASY
ANSWER
1/2
EASYMathematics
These are circles that have the same center.
EASY
ANSWER
concentric circles
EASYCommunication
The modulated peak value of a signal is 125V and the unmodulated carrier value is 85V. What is the modulation index?
EASY
ANSWER
0.47
EASYCommunication
A mismatched transmission line is also referred to as a ___________ line.
EASY
ANSWER
resonant
EASYCommunications
It is the ratio of the speed of propagation on a line to that of light in free-space.
EASY
ANSWER
velocity factor
EASYElectronics
Which of the following is the most widely used UTP cable that can carry baseband data at rates up to 100 Mbps at a range up to 100m?
EASY
ANSWER
CAT 5
EASYGEAS
This component measures the pulling (or pushing) action perpendicular to the section
EASY
ANSWER
Axial forces
EASYGEAS
It is the point at which there is an appreciable elongation of the material without any corresponding increase of load
EASY
ANSWER
Yield point
average
averageCOMMUNICATION
Determine the phase-shift represented by a 75 ns delay of a 4 MHz signal to a 75-ft cable with a dielectric constant of 2.3.
EASY
ANSWER
108 degrees
average
EASYSOLUTION
Θ = 360 td / T T =1/f = 1 / 4MHz = 250 ns Θ = 360 (75) / 250 = 108 degrees
average
EASYEST
The input to an FM receiver has a S/N of 2.8. What is the frequency deviation caused by the noise if the modulating frequency is 1.5KHz and the permitted deviation is 4KHz?
average
EASY
ANSWER
547.8 Hz
average
EASYSolution
= fm f= sin -1 N/S f= sin -1 1/2.8 f= 0.3652 = (0.3652)(1.5KHz) = 547.8 Hz
average
EASYEST
What circuit is used to return the frequency response of a signal to its normal, “flat” level?
average
EASY
ANSWER
de-emphasis
average
EASYMathematics
Let k be the number of gallons of a 50% silver nitrate solution that are added to 15 gallons of a 30% silver nitrate solution to produce a 35% silver nitrate solution. Let w be the number of sides of a regular polygon whose degree measure of one of the exterior angles is 8. Find the value of (k+w).
average
EASY
ANSWER
50
average
EASYMathematics
In how many distinct points do the real graphs of
Intersect?
average
EASY
ANSWER
2
average
EASYGEAS
It is the maximum safe stress that a material can carry
average
EASY
ANSWER
working stress
average
EASYCommunications
It is the most common means of overcoming the problems of quantizing error and noise.
average
EASY
ANSWER
companding
average
EASY
Electronics
It can be used in a single-stage oscillator circuit to provide a pulse signal suitable for digital-circuit applications.
average
EASY
ANSWER
UJT or unijunction transistor
average
averageGEAS
A large pipe, called a penstock in hydraulic work, is 1.5 m in diameter. It is composed of wooden staves bound together by steel hoops, each 300 sq. Millimetre in cross-sectional area, and is used to conduct water from a reservoir to power a house. If the maximum tensile stress permitted in the hoops is 130 MPa, what is the maximum spacing between hoops under a head of water of 30 m?
AVErage
ANSWER
L = 177 mm
AVErage
SOLUTION
(1000)(9.81)(30)(1.5)L = 2(300x10^-6)(130x10^6)L = 177 mm
averageGEAS
At what angular velocity will the stress in a rotating steel ring equal to 150 MPa if its mean radius is 220 mm? The density of the steel is 7.85 Mg/m^3.
AVErage
ANSWER
628 rad/s
AVErage
ANSWER
ω = (1/0.22)(150x10^6 / 7850)^(1/2) ω = 628 rad/s
Difficult
difficultCOMMUNICATION
It means that the characteristics and performance of an antenna are the same whether the antenna is radiating or intercepting an electromagnetic signal.
EASY
ANSWER
antenna reciprocity
difficult
EASYEST
Which of the following methods is used to lower the resonant frequency of a shortened vertical antenna?
difficult
EASY
ANSWER
top hat loading
difficult
EASYEST
Calculate the gain (relative to an isotropic) of a parabolic antenna that has a diameter of 3 m, an efficiency of 60% and operates at a frequency of 4 GHz.
difficult
EASY
ANSWER
39.8 dBi
difficult
EASYSOLUTION
G = 2 D2/ 2
= 3x108/ 4MHz = 0.075 m
G = 0.62(3)2
0.0752
G= 9474.8 G = 10 log 9474.8G = 39.8 dBi
difficult
EASYMathematics
Team A and B play a series of games. The first to win two games wins the series and Team A has a 70% chance of winning any game. What is the probability that Team A wins the series?
difficult
EASY
ANSWER
0.784
difficult
EASYMathematics difficult
EASY
ANSWER
49
difficult
EASYCommunication
It is a phenomenon caused by any support insulators used at the ends of the wire antenna.
difficult
EASY
ANSWER
end effect
difficult
EASYElectronics difficult
EASY
ANSWER
16.2 Hz
difficult
EASYSOLUTION
difficult
EASYGEAS
A pipe carry steam at 3.5 MPa has an outside diameter of 450 mm and a wall thickness of 10 mm. A gasket is inserted between the flange at one end of the pipe and a flat plate use to cap the end. How many 40-mm-diameter bolts must be used to hold the cap on if the allowable stress in the bolts is 80 MPa, of which 55 MPa is the initial stress?
difficult
EASY
ANSWER
N = 17
difficult
EASY
SOLUTION
N = (3.5x10^6)(0.45 – 2x0.01)^2 / [(0.04^2)(88–55)x10^6] N= 16.18 round upN = 17
difficult
DifficultGEAS
A pipe carry steam at 3.5 MPa has an outside diameter of 450 mm and a wall thickness of 10 mm. A gasket is inserted between the flange at one end of the pipe and a flat plate use to cap the end. What circumferential stress is developed in the pipe?
Difficult
ANSWER
= 75.3 MPa
Difficult
SOLUTION
σ = (3.5)(450 – 2x10) / [2(10)] = 75.3 MPa
DifficultGEAS
A steel rod having a cross-sectional area of 300 sq. Meters and a length of 150 m is suspended vertically from one end. It supports a tensile load of 20 kN at the lower end. If the unit mass of steel is 7850 kg/m^3 and E = 200x10^3 MN/m^2, find the total elongation of the rod.
Difficult
Answer
δ = 54.3 mm
Difficult
ANSWER
δ = [(7850)(9.8)(150^2) / 2(200X10^9)] + [(20000)(150)(1000^2) / 300(200X10^9)]
δ = 54.3 mm