Same number of books are placed in four book cases as shown. Which bookcase is most likely to topple forward if pulled a little at the top towards right:
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Same number of books are placed in four book cases as shown. Which bookcase is most likely to topple forward if pulled a little at the top towards right:

G1 Physics · Accepted Answer

Use τ⃗=r⃗×F⃗ and Στ=Iα. For equilibrium, set ΣF=0 and Στ=0; for impending toppling take moments about the contact edge. Substituting the stated dimensions/forces gives Image 3.