Einthoven's triangle, what is the value of lead III when lead I = 2 mv and Lead II = 1 mv: (A) 1, (B) 2, (C) 3, (D) 4
Answer is A. Einthovens formula states that the sum of voltages from lead I plus those from lead III minus those from lead II is zero. Lead I+III-II=0 This is based on the principle that the sum.of the voltages in a closed path equals zero. Because the positive and negative electrodes of lead II are reversed. So it is subtracted instead of adding.