Import Question JSON

Current Question (ID: 9771)

Question:

$\text{The friction between the front foot and the back foot when walking on a horizontal surface is, respectively:}$

Options:

1. $\text{Forward, forward}$
2. $\text{Backward, backward}$
3. $\text{Forward, backward}$
4. $\text{Backward, forward}$

Solution:

$\text{Hint: Friction force opposes the relative motion of the surfaces of contact.}$ $\text{Step 1: Analyse the situation.}$ $\text{When a person walks forward, we need to consider the motion of each foot relative to the ground:}$ $\text{For the back foot (pushing foot):}$ $\text{- The foot pushes backward against the ground}$ $\text{- By Newton's third law, the ground exerts a forward friction force on the foot}$ $\text{- This forward friction on the back foot propels the person forward}$ $\text{For the front foot (landing foot):}$ $\text{- The foot tends to slide forward when it lands}$ $\text{- Friction opposes this forward sliding motion}$ $\text{- Therefore, friction acts backward on the front foot}$ $\text{The friction forces are: Front foot - backward, Back foot - forward}$ $\text{This corresponds to option 4: Backward, forward}$

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
}