Question

A block is hung by a string from the inside roof of a van. When the van goes straight ahead at a speed of 26 m/s, the block hangs vertically down. But when the van maintains this same speed around an unbanked curve (radius = 135 m), the block swings toward the outside of the curve. Then the string makes an angle θ with the vertical. Find θ

Answer 1

M V^2/R = M g tan θ
is the centripetal force provided by the inclined string.

M cancels out. Solve for θ.

θ = arctan [V^2/(Rg)]