Import Question JSON

Current Question (ID: 14528)

Question:

Which of the following correctly explains a phase/event in cardiac cycle in a standard electrocardiogram?

Options:

1. QRS complex indicates atrial contraction
2. QRS complex indicates ventricular contraction
3. Time between S and T represents atrial systole
4. P-wave indicates the beginning of ventricular contraction

Solution:

In a standard electrocardiogram (ECG), the QRS complex represents the depolarization (contraction) of the ventricles. It consists of three waves: Q, R, and S. The Q wave is the first negative deflection, the R wave is the first positive deflection, and the S wave is the first negative deflection after the R wave. The QRS complex is followed by the T wave, which represents the repolarization (relaxation) of the ventricles. The P wave in the ECG represents the depolarization (contraction) of the atria. The time between the S and T waves represents the period of ventricular ejection (ventricular systole), not atrial systole.

Import JSON File

Upload a JSON file containing LaTeX/MathJax formatted question, options, and solution.

Expected JSON Format:

{
  "question": "The mass of carbon present in 0.5 mole of $\\mathrm{K}_4[\\mathrm{Fe(CN)}_6]$ is:",
  "options": [
    {
      "id": 1,
      "text": "1.8 g"
    },
    {
      "id": 2,
      "text": "18 g"
    },
    {
      "id": 3,
      "text": "3.6 g"
    },
    {
      "id": 4,
      "text": "36 g"
    }
  ],
  "solution": "\\begin{align}\n&\\text{Hint: Mole concept}\\\\\n&1 \\text{ mole of } \\mathrm{K}_4[\\mathrm{Fe(CN)}_6] = 6 \\text{ moles of carbon atom}\\\\\n&0.5 \\text{ mole of } \\mathrm{K}_4[\\mathrm{Fe(CN)}_6] = 6 \\times 0.5 \\text{ mol} = 3 \\text{ mol}\\\\\n&1 \\text{ mol of carbon} = 12 \\text{ g}\\\\\n&3 \\text{ mol carbon} = 12 \\times 3 = 36 \\text{ g}\\\\\n&\\text{Hence, 36 g mass of carbon present in 0.5 mole of } \\mathrm{K}_4[\\mathrm{Fe(CN)}_6].\n\\end{align}",
  "correct_answer": 4
}