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Course: MCAT > Unit 3

Lesson 1: Chemical and physical sciences practice passage questions

Capacitors in electrocardiography monitors


A heart monitor detects the functional soundness of the patient’s heart. Nodes are attached to a patient’s skin, which in turn is able to pick up cardiac electrical activity. These nodes then relay this information to the main monitor, which displays it accordingly.
A technician is working at a hospital with similar machines, referred to as electrocardiography (ECG) monitors. The monitoring equipment that the hospital uses has a single 12F capacitor within. When the ECG is in use, the 12F capacitor is subjected to a voltage of 3V.
The monitoring equipment functions properly during the first portion of the day. However, later in the day the 12F capacitor in one of the ECG monitors burns out.
After looking in the electronics storeroom, the technician realizes the hospital does not have any extra working 12F capacitors available. All the hospital has are the following capacitors:
Figure 1. The capacitors available at the technician’s disposal.
The technician realizes that there may be a way to fix the ECG using the available capacitors.
Of the available capacitors, which could you connect in parallel to replace one of the burned out capacitors?
Choose 1 answer: