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STD 11 - 4.2 friction — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 11 - 4.2 friction4 Marks
MCQ
A rectangular block has a square base measuring $a \times a$ and its height is $h$. It moves on a  horizontal surface in a direction perpendicular to one of the edges.  The coefficient of  friction is $\mu$. It will topple if
  • A
    $\mu > \frac{h}{a}$
  • ✓
    $\mu > \frac{a}{h}$
  • C
    $\mu > \frac{2a}{h}$
  • D
    $\mu > \frac{a}{2h}$
✓

Answer

Correct option: B.
$\mu > \frac{a}{h}$
b
$\mathrm{C}:$ center of mass

$\tau_{C}=\mathrm{f} \frac{\mathrm{h}}{2}-\mathrm{N} \frac{\mathrm{a}}{2} \geq 0$ for toppling

$\mu \mathrm{N} \frac{\mathrm{h}}{2}>\mathrm{N} \frac{\mathrm{a}}{2}$      $\mu>\frac{\mathrm{a}}{\mathrm{h}}$

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