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1 Kinematics and Statics
τ 1 = (mg)(BD) = (mg)
BD
BG
BG
= mg
L
2
cos α
(1)
The friction with the ground, which acts toward right produces a counterclockwise torque τ 2 :
τ 2 = (μ mg)AC = μmg
AC
AB
AB = μmgL sin α
(2)
For limiting equilibrium τ 1 = τ 2
∴ mg
L
2
cos α = μmgL sin α
∴ μ =
1
2
cot α
1 Kinematics and Statics
τ 1 = (mg)(BD) = (mg)
BD
BG
BG
= mg
L
2
cos α
(1)
The friction with the ground, which acts toward right produces a counterclockwise torque τ 2 :
τ 2 = (μ mg)AC = μmg
AC
AB
AB = μmgL sin α
(2)
For limiting equilibrium τ 1 = τ 2
∴ mg
L
2
cos α = μmgL sin α
∴ μ =
1
2
cot α