JEE Physics · Hard

Rigid Body Dynamics: JEE — Torque Equilibrium MCQ

Solve this quality-checked JEE multiple-choice question, then review the correct answer and explanation.

Timer-based practiceDetailed answer reviewMobile-friendly flow
JEE — Torque EquilibriumHardQuestion 30367

Question

A uniform ladder (mass M, length L) leans against a smooth wall, foot on rough floor. For equilibrium, the torque equation about the base gives the wall reaction N_w as:
  1. A
    MgL cosθ/(2 sinθ)
  2. B
    Mg tanθ/2
  3. C
    Mg/(2 tanθ)
    Correct
  4. D
    Mg cosθ/2

Correct answer

Mg/(2 tanθ)

Explanation

Taking torques about the base: N_w × L sinθ = Mg × (L/2) cosθ. N_w = Mg cosθ/(2 sinθ) = Mg/(2 tanθ).