ele 100 quiz 6
Transistor is a ___________________________.
3-terminal device
Calculate the voltage across the secondary coil of the transformer shown below.
36 V
A transformer which has 1380 turns in its primary coil is to be used to convert the mains voltage of 230 V to operate a 6 V bulb. How many turns should the secondary coil of this transformer have?
36 turns
AC frequency in US(United States);
60 Hz
What is the primary voltage applied to the transformer shown in the figure here?
90V
Will a transformer work with direct current (d.c.) or alternating current (a.c.)?
AC only
Commonly used transistor/s is/are ________________________.
Both A & B
_________________is the is the generation of current due to relative motion between a wire and a magnetic field.
Electromagnetic Induction
The terminals of a BJT transistor are called;
Emitter, Base and Collector
A light emitting diode absorbs light to generate electricity.
False
Current does not flow in a forward biased diode.
False
Diode conducts in both directions.
False
Integrated circuits are devices made up of only resistors.
False
Step-up transformers are located near to end user.
False
The heavier the doping in a semiconductor, lower is the conductivity.
False
Unit of Inductance is _________________.
Henry
Electrical Generator performs which kind of energy conversion?
Mechanical Energy to Electrical Energy
MOSFET stands for;
Metal Oxide Semiconductor Field Effect Transistor
Who discovered the operating principle of electromagnetic generators?
Michael Faraday
The machine that converts electrical energy to mechanical energy is called a:
Motor
What is meant by a step down transformer?
One where the output voltage is smaller than the input voltage
Converting AC to DC is accomplished by the process of ___________________.
Rectification
Identify the semiconductor.
Silicon
In a transformer, the primary coil has twice as many loops as the secondary coil. This is a __________ transformer.
Step-down
A transistor is used for __________________________.
Switching voltages & currents and also for amplifying small signals into large currents.
The faster the coil of a generator rotates through the magnetic field the______________.
The higher the output voltage.
A P-type semiconductor material has a shortage of electrons with vacancies called holes.
True
According to principle of electro-magnetic induction, generator produces voltage when there is a changing magnetic field.
True
Addition of impurities to the pure semiconductor is called Doping.
True
For a transformer, power is conserved at the primary (imput) and the secondary (output).
True
Inductor is an element which is a coil of wire wound around an iron core.
True
Inductors add up like resistors in series and parallel.
True
Organic LED's give off very nice vibrant colors and are flexible.
True
Semiconductors are materials that have conductivity in between conductors and insulators.
True
The operation of an electrical generator relies on electromagnetic induction.
True
The size of an integrated circuit is part of the reason for the importance of ICs in electronics.
True
AC generators are also called _______________, since they produce an alternating current.
alternators
The positive end of a diode is called the ____________ and the negative end is called the _____________.
anode and cathode
Increasing the number of turns of wire on the secondary of a transformer will___________.
decrease the secondary current and increase the primary current
An N-type semiconductor has excess of __________________.
electrons
An P-type semiconductor has excess of ______________.
holes
Electromagnetic induction is a term used to describe___________.
production of electric potential due to change in magnetic flux
When the current through a coil reverses direction, the magnetic field around the coil _________.
reverses its direction
An integrated circuit is made on a ______________piece of Silicon called the chip.
single