MS Master of Electrical Engineering 2

Question 1

What is the primary advantage of using a Phase-Locked Loop (PLL) in communication systems?

Accepted Answer

Frequency synthesis and clock recovery

Answer

A PLL is primarily used for frequency synthesis and clock recovery by locking its output frequency to an input reference signal.

Question 2

Which law governs the relationship between magnetic flux density (B), permeability (μ), and magnetic field intensity (H)?

Accepted Answer

B = μH

Answer

B = μH is the fundamental constitutive relation for magnetic materials, where μ is the permeability of the medium.

Question 3

In a BJT transistor operating in the active region, what is the relationship between collector current (Ic) and base current (Ib)?

Accepted Answer

Ic = β × Ib

Answer

In the active region, collector current equals the current gain (β, or hFE) multiplied by the base current.

Question 4

What type of feedback reduces output impedance in an amplifier?

Accepted Answer

Voltage-series feedback

Answer

Voltage-series (voltage-shunt) feedback senses output voltage and reduces output impedance while increasing input impedance.

Question 5

What is the function of a snubber circuit in power electronics?

Accepted Answer

Suppress voltage spikes and reduce switching losses

Answer

A snubber circuit suppresses high-voltage transients and reduces switching losses that occur during rapid on/off transitions of power devices.

MS - Master of Science Practice Test