Slide 1

EASYEASYMATHEMATICS

He was known as the father of modern geometry

EASYANSWER

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

EASYANSWER

microstrip

EASYEST

One complete revolution around a Smith Chart represents _________ wavelengths.

EASYANSWER

1/2

EASYMathematics

These are circles that have the same center.

EASYANSWER

concentric circles

EASYCommunication

The modulated peak value of a signal is 125V and the unmodulated carrier value is 85V. What is the modulation index?

10EASYANSWER

0.47

EASYCommunication

A mismatched transmission line is also referred to as a ___________ line.EASYANSWER

resonant

EASYCommunications

It is the ratio of the speed of propagation on a line to that of light in free-space.

EASYANSWER

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?

EASYANSWER

CAT 5

EASYGEAS

This component measures the pulling (or pushing) action perpendicular to the section

EASYANSWER

Axial forces

EASYGEAS

It is the point at which there is an appreciable elongation of the material without any corresponding increase of load

EASYANSWER

Yield point

averageaverageCOMMUNICATION

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.

EASYANSWER

108 degrees

averageEASYSOLUTION

= 360 td / TT =1/f = 1 / 4MHz = 250 ns = 360 (75) / 250 = 108 degrees

averageEASYEST

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?

averageEASYANSWER

547.8 Hz

averageEASYSolution

= fm = sin -1 N/S = sin -1 1/2.8 = 0.3652 = (0.3652)(1.5KHz) = 547.8 Hz

averageEASYEST

What circuit is used to return the frequency response of a signal to its normal, flat level?

averageEASYANSWER

de-emphasis

averageEASYMathematics

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).

averageEASYANSWER

50averageEASYMathematics

In how many distinct points do the real graphs of

Intersect?

average

33EASYANSWER

2

averageEASYGEAS

It is the maximum safe stress that a material can carry

averageEASYANSWER

working stress

averageEASYCommunications

It is the most common means of overcoming the problems of quantizing error and noise.

averageEASYANSWER

companding

averageEASYElectronics

It can be used in a single-stage oscillator circuit to provide a pulse signal suitable for digital-circuit applications.

averageEASYANSWER

UJT or unijunction transistor

averageaverageGEAS

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?

AVErageANSWER

L = 177 mm

AVErageSOLUTION

(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.

AVErageANSWER

628 rad/s

AVErageANSWER

= (1/0.22)(150x10^6 / 7850)^(1/2) = 628 rad/s

DifficultdifficultCOMMUNICATION

It means that the characteristics and performance of an antenna are the same whether the antenna is radiating or intercepting an electromagnetic signal.

EASYANSWER

antenna reciprocity

difficultEASYEST

Which of the following methods is used to lower the resonant frequency of a shortened vertical antenna?

difficultEASYANSWER

top hat loading

difficultEASYEST

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.

difficultEASYANSWER

39.8 dBi

difficultEASYSOLUTION

G = 2 D2/ 2 = 3x108/ 4MHz = 0.075 m

G = 0.62(3)2 0.0752G= 9474.8G = 10 log 9474.8G = 39.8 dBi

difficultEASYMathematics

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?

difficultEASYANSWER

0.784

difficultEASYMathematics

difficult

57EASYANSWER

49difficultEASYCommunication

It is a phenomenon caused by any support insulators used at the ends of the wire antenna.

difficultEASYANSWER

end effect

difficultEASYElectronics

difficult

EASYANSWER

16.2 HzdifficultEASYSOLUTION

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?

difficultEASYANSWER

N = 17

difficultEASYSOLUTION

N = (3.5x10^6)(0.45 2x0.01)^2 / [(0.04^2)(8855)x10^6] N= 16.18 round upN = 17

difficultDifficultGEAS

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?

DifficultANSWER

= 75.3 MPa

DifficultSOLUTION

= (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.

DifficultAnswer

= 54.3 mm

DifficultANSWER

= [(7850)(9.8)(150^2) / 2(200X10^9)] + [(20000)(150)(1000^2) / 300(200X10^9)]

= 54.3 mm