Description : Why is the physical length of a coaxial cable transmission line shorter than its electrical length? A. Skin effect is less pronounced in the coaxial cable B. RF energy moves slower along the ... higher in the parallel feed line D. The characteristic impedance is higher in the parallel feed line
Last Answer : B. RF energy moves slower along the coaxial cable
Description : The physical layer provides __________ a. mechanical specifications of electrical connectors and cables b. electrical specification of transmission line signal level c. specification for IR over optical fiber d. all of the mentioned
Last Answer : d. all of the mentioned
Description : The physical layer provides __________ A. mechanical specifications of electrical connectors and cables B. electrical specification of transmission line signal level C. specification for IR over optical fiber D. all of the mentioned
Last Answer : D. all of the mentioned
Description : What specifications does physical layer provides __________. A. mechanical specifications of electrical connectors and cables B. electrical specification of transmission line signal level C. specification for IR over optical fiber D. all of the mentioned
Description : The physical layer provides __________ a) mechanical specifications of electrical connectors and cables b) electrical specification of transmission line signal level c) specification for IR over optical fiber d) all of the mentioned
Last Answer : d) all of the mentioned
Description : Speaker is a device that __________. A. convert current variations into sound waves B. none of these C. convert electrical energy to mechanical energy D. convert sound waves into current and voltage
Last Answer : A. convert current variations into sound waves
Description : Which of the following determines the acoustic behavior of gases? A. Density B. Pressure C. Temperature D. All of the choices
Last Answer : D. All of the choices
Description : The physical layer translates logical communication requests from the ______ into hardware specific operations. a. data link layer b. network layer c. trasnport layer d. application layer
Last Answer : a. data link layer
Description : Which address is used to identify a process on a host by the transport layer? a) physical address b) logical address c) port address d) specific address
Last Answer : c) port address
Description : State weather the following statement is true or false for Token Bus 1).It is a linear or tree- shaped cable onto which the stations are attached. 2). the token propagates around the logical ring, with only the token holder ... 3. false C. 1. false, 2. false, 3. false D. 1. true, 2. true, 3. false
Last Answer : D. 1. true, 2. true, 3. false
Description : Which is an effect of the hormone estrogen? A) accumulation of a fat layer beneath the skin B) pelvic girdle grows wider C) breast development D) egg maturation and menstrual cycle control E) All of the choices are estrogen effects.
Last Answer : E) All of the choices are estrogen effects.
Description : What device in a waveguide system used for stopping or diverting electromagnetic wave as desired? A. Mechanical switch B. Electric switch C. Push-button switch D. Waveguide switch
Last Answer : D. Waveguide switch
Description : In ATM, the _____ layer defines thetransmission medium,bit transmission,encoding, and electrical-to-optical transformation. A) physical B) ATM layer C) AAL D) none of the above
Last Answer : physical
Description : The layer that transmits data in the form of bit streams using electrical and mechanicalsystems is in the OSI model. a. Physical layer b. Transport Layer c. Network Layer d. Data Link Layer
Last Answer : a. Physical layer
Description : The _____layer defines the electrical and physical specifications for devices: a) Data Link Layer b) Presentation Layer c) Physical Layer d) None of These
Last Answer : c) Physical Layer
Description : What is the radiation characteristic of a dipole antenna? A. Omnidirectional B. Bidirectional C. Unidirectional D. Hemispherical
Last Answer : B. Bidirectional
Description : What significant element of sound refers to its characteristic tonal quality? A. Pitch B. Tempo C. Rhythm D. Timbre
Last Answer : D. Timbre
Description : What is the input impedance of a transmission line if its characteristic impedance is 300 Ω and the load is 600 Ω? Assume a quarter wavelength section only. A. 150 kΩ B. 150 mΩ C. 150 Ω D. 2 Ω
Last Answer : C. 150 Ω
Description : What is the term for the ratio of actual velocity at which a signal travels through a line to the speed of light in a vacuum? A. Velocity factor B. Characteristic impedance C. Surge impedance D. Standing wave ratio
Last Answer : A. Velocity factor
Description : What is the meaning of the term velocity factor of a transmission line? A. The ratio of the characteristic impedance of the line to the terminating impedance B. The index of shielding for coaxial ... The velocity of the wave on the transmission line divided by the velocity of light in a vacuum.
Last Answer : D. The velocity of the wave on the transmission line divided by the velocity of light in a vacuum.
Description : Attack is a sound characteristic that refers to the way a sound begins. Which of the following is NOT an attack of sound? A. Hard B. Soft C. Crisp D. Simple
Last Answer : D. Simple
Description : What sound characteristic relates to a sonic time pattern? A. Tempo B. Attack C. Rhythm D. Timbre
Last Answer : C. Rhythm
Description : What is the velocity factor of coaxial cable with a characteristic impedance of 50Ω and capacitance of 30pF/ft and inductance of 75 nH/ft? A. 0.58 B.0.68 C. 0.98 D. 0.81
Last Answer : B.0.68
Description : What is the characteristic impedance of a coaxial line with the following data: inner diameter = 0.2 in., center conductor diameter = 0.06 in., insulation = Teflon. A. 200Ω B. 75Ω C. 50Ω D. 150Ω
Last Answer : C. 50Ω
Description : What is the characteristic impedance of a two-wire line with the following data: diameter = 0.023in., spacing =0.5 in., insulation = PE.? A. 300Ω B. 250Ω C. 305Ω D. 301Ω
Last Answer : D. 301Ω
Description : What is the meaning of the term velocity factor of a transmission line? A. The index of shielding for coaxial cable B. The velocity of the wave on the transmission line multiplied by the velocity of ... The velocity of the wave on the transmission line divided by the velocity of light in a vacuum
Last Answer : D. The velocity of the wave on the transmission line divided by the velocity of light in a vacuum
Description : Referred to the dielectric constant of a transmission line material. A. Inductance and capacitance B. Velocity factor C. Characteristic impedance D. Propagation velocity
Last Answer : B. Velocity factor
Description : What is the characteristic impedance of a single wire with a diameter d= 0.25 mm placed at the center between grounded parallel planes separated by 1 mm apart. The wire is held by a material with a velocity factor of 0.75. A. 85 Ω B. 63 Ω C. 50 Ω D. 75 Ω
Last Answer : D. 75 Ω
Description : Transmission lines when connected to antenna have A. capacitive load B. resistive load whose resistance is less than characteristics impedance C. resistive load at the resonant frequency D. resistive load whose resistance is greater than the characteristic impedance of the line
Last Answer : C. resistive load at the resonant frequency
Description : If the terminating impedance is exactly equal to the characteristic impedance of the transmission line the return loss is ___________. A. zero B. one C. infinite D. None of these
Last Answer : C. infinite
Description : Why Physical properties of nylon and leather make them good choices for shoelaces?
Last Answer : Feel Free to Answer
Description : Given below are some characteristics of logical argument. Select the code which expresses a characteristic which is not of inductive in character. (A) The conclusion is claimed to follow from ... conclusively follows from its premises. (D) The conclusion is based on observation and experiment
Last Answer : (C) The conclusion conclusively follows from its premises.
Description : Which of the following is not a major benefit of fiber-optic cable? a. Immunity from interference b. No electrical safety problems c. Excellent data security d. Lower cost
Last Answer : b. No electrical safety problems
Description : What is the usual electrical length of a driven element in an HF beam antenna? A. ¼ wavelength B. ¾ wavelength C. ½ wavelength D. 1 wavelength
Last Answer : C. ½ wavelength
Description : Increasing the electrical length of an antenna means A. add an inductor in parallel B. add a capacitor in series C. add an inductor series D. add a resistor is series
Last Answer : C. add an inductor series
Description : What is the electrical wavelength of a 500 MHz signal? A. 60 centimeters B. 6 meters C. 0.06 meter D. 60 meters
Last Answer : A. 60 centimeters
Description : What is the effect of adding a capacitor in series with an antenna? A. The antenna’s resonant frequency will increase B. The antenna’s resonant frequency will decrease C. The antenna will be physically 5% longer than its electrical length D. A capacitor is never added in series with an antenna
Last Answer : A. The antenna’s resonant frequency will increase
Description : The solar cycle repeats the period of great electrical disturbance approximately every A. 11 years B. 10 years C. 9 years D. 8 years
Last Answer : A. 11 years
Description : What is the proper procedure for suppressing electrical noise in a mobile station? A. Apply shielding and filtering where necessary B. Insulate a all plain sheet metal surfaces from each other C. ... -static spray liberally to all nonmetallic D. Install filter capacitors in series with all dc wiring
Last Answer : A. Apply shielding and filtering where necessary
Description : What do you call the electrical conduction in a photosensitive material which is not exposed to radiation? A. Dark conductance B. Pure conductance C. Black out D. Super conductance
Last Answer : A. Dark conductance
Description : What organization has published safety guidelines for the maximum limits of RF energy near the human body? A. The American National Standards Institute (ANSI). B. The Environmental Protection ... Communications Commission (FCC). D. The Institute Of Electrical and Electronics Engineers (IEEE).
Last Answer : A. The American National Standards Institute (ANSI).
Description : Which coaxial connector is a more complex and expensive but do a better job in maintaining the electrical characteristics of the cable through the interconnections? A. N-type connector B. F-type connector C.BNC D. PL-259
Last Answer : A. N-type connector
Description : Which one is not the basic electrical protection measures in the Philippine Electronics Code? A. Voltage/ current limiting and interrupting B. Undergrounding C. Grounding and bonding D. Shielding
Last Answer : B. Undergrounding
Description : Power is a _____________ amount of energy used in specific period of time A. large B. definite C. electrical D. relative
Last Answer : B. definite
Description : ECE Board Exam March 1996 The potential difference between any exposed structured to ground in any electrical installation should not exceed _________ volts RMS. A. 10 B. 45 C. 0 D. 30
Last Answer : B. 45
Description : The angle of elevation of the antenna beam is 20°. Calculate the transmission-path distance for an ionospheric transmission that utilizes a layer of virtual height 200 km. Use flat-earth approximation. A. 966 km B. 2100 km C. 1100 km D. 405 km
Last Answer : C. 1100 km
Description : What ionospheric layer has a daytime approximate critical frequency of 8 MHz? A. F2 layer B. F1 layer C. E layer D. D layer
Last Answer : A. F2 layer
Description : What is the approximate single-hop nighttime range of F2 layer? A. 3840 km B. 3000 km C. 4130 km D. 2350 km
Last Answer : C. 4130 km
Description : What is the approximate critical frequency of the E layer? A. 4 MHz B. 5 MHz C. 6 MHz D. 3 MHz
Last Answer : A. 4 MHz
Description : A radio communications link is to be established via the ionosphere. The maximum virtual height of the layer is 100 km at the midpoint of the path and the critical frequency is 2 MHz. The distance between stations is 600 ... optimum working frequency? A. 6.32 MHz B. 2.1 MHz C. 5.4 MHz D. 1.8 MHz
Last Answer : C. 5.4 MHz