ELEX Pre-Board Exam 18

What composes all matter whether a liquid, solid or gas?

• Atoms
• Electrons
• Protons
• Neutrons

The Piezoelectric effect in a crystal is _____.

• a voltage developed because of mechanical stress
• a change in resistance because of temperature
• a change of frequency because of temperature
• none of the choices

A unit impulse function on differentiation results in

• unit doublet
• unit triplet
• unit parabolic function
• unit ramp function

In the JK flip-flop a High on the K input during the clock transition will yield an output of

• Q=low
• Q-toggle
• Q=high
• not possible to determine

What class of operation has little use in general purpose amplifiers but is used in high frequency oscillators?

• Class A
• Class AB
• Class B
• Class C

Feedback factor is always

• less than 1
• equal to 1
• more than 1
• zero

Arrival of a clock signal at the clock inputs of different flip-flops at different times as a result of propagation delays.

• clock transition
• buffer address
• clock skew
• none of the choices

With double the number of turns by the same length and area, the inductance is

• the same
• doubled
• quartered
• quadrupled

An ideal op-amp has

• infinite input and output impedance
• very low input and output impedance
• low input impedance and infinite output impedance
• infinite input impedance and zero output impedance

What is the most important factor of a power transistor?

• impedance matching
• output resistance
• mounting
• heat dissipation