ELE 100 in class Quiz 6
What is the primary voltage applied to the transformer shown in the figure here?
1.2 A, 15Ohms, 5:1 90V
Transistor is a
3-terminal device
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 is US
60Hz
Will a transformer work with direct current (d.c.) or alternating current?
AC only
AC generators are also called______, since they produce an alternating current.
Alternators
Commonly used transistor/s is/are
Both A & B
______________is the generation of current due to relative motion between a wire and magnetic field.
Electromagnetic Induction
An N-Type semiconductor has excess of ___________
Electrons
The terminals of a BJT transistor are called:
Emitter, Base and Collector
Step-up transformers are located near to end user
FALSE
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
The heavier the doping in a semiconductor, lower is the conductivity.
False
Units 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 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
Calculate the voltage across the secondary coil of the transformer shown below....
Primary coil- 180 turns, 12 V a.c, secondary coild- 540 turns 36 V
Electromagnetic induction is a term used to describe____________.
Production of electric potential due to change in magnetic flux
Converting AC to DC is accomplished by the process of.....
Rectification
Identify the semiconductor
Silicon
An integrated circuit is made on a ________- piece of silicon called the chip.
Single
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.
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 primary (input) and 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 a 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 IC's in electronics
True
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.
The faster the coil of a generator rotates through the magnetic field the
higher the output voltage
A P-Type semiconductor has excess of _______
holes
When the current through a coil reverses direction, the magnetic field around the coil...
reverses its direction
