BTC Biomedical Instrumentation & Electrical Fundamentals 2

Question 1

A pressure transducer in a patient monitoring system converts mechanical pressure into which type of output signal?

Accepted Answer

An electrical signal proportional to pressure

Answer

Optical pulses

Answer

Digital binary codes directly

Answer

Magnetic flux changes

Question 2

In biomedical signal conditioning, which circuit stage is primarily responsible for removing unwanted frequency components from a physiological signal before digitization?

Accepted Answer

Filter stage

Answer

Amplifier stage

Answer

Sample-and-hold stage

Answer

Digital-to-analog converter

Question 3

Common Mode Rejection Ratio (CMRR) is a critical specification for biomedical amplifiers because it describes the amplifier's ability to:

Accepted Answer

Reject noise signals common to both inputs

Answer

Increase the frequency bandwidth of the signal

Answer

Convert analog signals to digital values

Answer

Match the impedance between stages

Question 4

An isolation transformer used in patient-care areas provides electrical isolation primarily to:

Accepted Answer

Prevent patient electrical shock by eliminating a direct ground reference

Answer

Step down voltage to safe low levels

Answer

Increase current capacity for medical equipment

Answer

Regulate output voltage automatically

Question 5

A biomedical technician needs to pass ECG signals (0.05–150 Hz) while blocking both very low-frequency baseline wander and high-frequency EMG noise. Which filter type should be used?

Accepted Answer

Band-pass filter

Answer

High-pass filter

Answer

Low-pass filter

Answer

Notch filter

Question 6

A 12-bit analog-to-digital converter (ADC) sampling a 0–5 V signal provides how many discrete output levels?

Accepted Answer

4,096

Answer

256

Answer

1,024

Answer

65,536

Question 7

Electromagnetic interference (EMI) from nearby surgical electrosurgical units most commonly causes which artifact in patient monitors?

Accepted Answer

High-frequency noise obscuring the waveform

Answer

Baseline flatline on ECG

Answer

Inverted QRS complexes

Answer

Slowed heart rate display