EE

53問 • 2年前

問題一覧

A transponder with a bandwidth of 400 MHz uses polarization diversity. If the wavelength allocated to transmit a single telephone channel is 4 kHz, how many telephone channels can be carried by the transponder?

100, 000

A room air conditioner is to be attached to an individual branch circuit. If the load is 12 A, what is the minimum size of branch circuit required?

15 А

Which of the following type of fault that used only the equivalent positive impedance of the circuit in the short-circuit calculation?

Double-line-to-ground fault

A washing machine is, in effect, an R-L circuit. If the machine takes 311 W and 4.5 A from a 155-V source when operating normally. Find its power factor.

0.60 lagging

Which of the following define the meaning of load factor?

The ratio of average load to maximum load

If the magnetic flux through a certain region is changing with time

an emf exist around the boundary

If the magnetic flux through a certain region is changing with time

an emf exist around the boundary

In a capacitor start motor, the capacitor is replaced by an inductor having the same reactance as in capacitor. Then the motor will

not start

Which of the following AC device is used to measure the angle between the voltage and its current?

phase angle meter

A resistor with resistance R1 and a resistor with resistance R2 are connected in parallel to an ideal battery with emf V. What is the rate of thermal energy generation in the resistor with resistance R1?

V2/R1

The grounded conductor is a/an Far Powerline Regisunde donductor.

intentionally

The resistance of a rod does NOT depend on_____

the shape of its cross-sectional area

When the amplitude of the oscillator in a series RLC circuit is doubled the_______

current amplitude is doubled

Which of the following protective device operates on the principle of Kirchoffs Current Law?

Differential Protective Relay

Which of the following will the effect of the electric shock in the human body depend on?

current flowing in the body

Which of these is NOT a simplex type of electronic communication?

Telephone

A good example of kinetic energy is provided by

a tornado

Current has units of

coulomb/second

The readings of the wattmeter will be the same in two-wattmeter method when

power factor is unity

Modern locomotives are powered by DC motors driven by DC generators. Those are, in turn, driven by diesel engines. Which of the following is the reason for using such a configuration instead of AC general-motor sets?

The DC configuration provides high torque and good incremental power at low speeds, and performs equally well at high speeds

What is the main reason that alternating current replaced direct current for general used?

AC voltages conveniently transformed.

What can usually be assumed as the driving or source voltage for fault and voltage calculations in per unit method?

1 p.u.

Which of the following is NOT a reason why single-phase induction motor run?

Two windings displaced from each other

Which of the following is normally a controlled grounding path for current flow?

high impedance circuit

The hazards exist only during the period of the time the

fault

At a certain location in Australia, it is necessary to supply 30kW of 60 Hz power. The only power sources available operate at 50 Hz. It is decided to generate the power by means of a motor-generator set consisting of a synchronous generator. How many poles should each of the two machines in order to convert 50 Hz to 60 Hz power?

A 10-pole synchronous motor coupled to a 12-pole synchronous generator

The resistance of a resistor 1 is twice of resistor 2. The two are connected in SERIES and a potential difference is maintained across the combination. What is the rate of themal energy generation in resistor 1? Answer is A

Twice that in resistor 2

What is the function of the surge tank in the hydro power plant?

Relieve water hammer pressures in the penstock pipe

Which of the following is NOT a property of magnetic field lines?

Magnetic field lines have no beginning and no ends.

Is the ground can be intentional or accidental? I. True Il. False

I only

In the oscillating LC circuit, then total stored energy is U. the maximum energy stored in the capacitor during one cycle is

U/2

What is the function of protective relays in the protection scheme?

sensing device

What is the electrical analog of a spring constant "k"?

The starting/ in rush current of the transformer is generally current.

The magnetic torque exerted on a flat current-carrying loop of wire by a uniform magnetic field B is.

maximum when the plane of the loop is perpendicular to B.

Two resistors are connected in parallel across a potential difference. The resistance of resistor A is twice that of resistor B. If the current carried by resiston a is I, then the current carried by B?

The growth rate of the energy consumption in our country is 6.9%. In how many years will the energy be quadrupled?

Which of the following is/are the MOST important factor/s to be considered in the selection of fuel for power plants? I. Cost of fuel Il. Calorific value of fuel

Both I and II

What is ACSR conductor stands for?

Aluminum Cable Steel Reinforced

The government agency created under Presidential Degree 269, whose additional mandates includes preparing electrical cooperatives in operating and competing under a deregulated electricity market.

National Electrification Administration

What is the maximum output of cellular transmitter?

3 W

The voltage regulation is an important factor in the design of

Feeder

What is/are the main reason/s for using high voltage in the transmission of power in grid systems? I. To transmit bulk power with minimum losses Il. To increase system reliability

I only

AC system has the following disadvantages over DC system

Charging current exist

What is the minimum branch circuit/ampacity of supply feeder for a window type air conditioning unit with 8-A rated load current with other load supplied?

Increasing the power output of alternator working in parallel to a large system, the operator must adjust

Govemor

Referring to the sending end voltage, what is the value of receiving end voltage at no load for medium transmission lines? I. higher II. Lesser III. Remains constant

I only

Where does a fluorescent lamp cannot be mounted that easily causes fire?

cellulose fiber

What is the PEC rule for the sizing wire and protection?

Wiring Design Rule

The process of modifying high frequency carrier with the information to be transmitted is called

Modulation

What is the frequency used in communication such as mobile phones?

UHF

Who is not been a member of the Board of Electrical Engineering?

Renato Cayetano

The coulomb force F, acts on two distances, r apart.What F proportional to

1/r^2

Math

Ashley Calica · 10問 · 2年前

Math