Thread: Another question of Equilibrium and Gravity - this is a tough topic for me

A wooden plank of uniform density is resting against a frictionless wall so that it makes an angle of θ to the ground as shown. What is the minimum value of the coefficient of friction, μ, between the ground and the plank in order to stop it slipping?

[Enter the variable θ using the string 'theta' (no quotes).]

not enough info. given.