Answer
given,
diameter of the pipe is = (14 ft)4.27 m
minimum speed of the skater must have at very top = ?
At the topmost point of the pipe the normal force will be equal to zero.
F = mg
centripetal force acting on the skateboard
[tex]F = \dfrac{mv^2}{r}[/tex]
equating both the force equation
[tex]mg = \dfrac{mv^2}{r}[/tex]
[tex]v = \sqrt{gr}[/tex]
r = d/2 = 14/ 2 = 7 ft
or
r = 4.27/2 = 2.135 m
g = 32 ft/s² or g = 9.8 m/s²
[tex]v = \sqrt{32 \times 7}[/tex]
v = 14.96 ft/s
or
[tex]v = \sqrt{9.8 \times 2.135}[/tex]
v = 4.57 m/s
