Answer:
θ = tan ( v²/gr)
Explanation:
This exercise we must find the angle of the string, for this we use Newton's second law
F = m a
Let's create a reference system with one vertical axis and the other in radial direction,
vertical axis
[tex]T_{y}[/tex] - W = 0
T_{y} = W
Radial axis
T_{r} = m a
As we are in a curve, they relate it to a switchboard
a = v² / r
We use trigonometry to find the components of the tension
cos θ = T_{y} / T
sin θ = T_{r} / T
T_{y} = T cos θ
T_{r} = T sin θ
we substitute
T cos θ = mg
T = m g / cos θ
T sin θ = m v² / r
(mg / cos θ) sin θ = m v² / r
tan θ = v² / g r
θ = tan ( v²/gr)