Posted by Kristina on .
A roller coaster reaches the top of the steepest hill with a speed of 3.0 . It then descends the hill, which is at an average angle of 40 and is 50.0 long. Estimate its speed when it reaches the bottom. Assume kinetic friction (uk) = 0.18 .

Physics 
Henry,
Vo = 3 m/s.
u(k) = 0.18.
A rt. triangle is formed:
r = 50 m. = hyp.
A = 40 Deg.
Y = 50*sin40 = 32.1 m. = h.
V^2 = Vo^2 + 2g*h.
V^2 = 3^2 + 19.6*32.1 = 638.2.
V = 25.3 m/s = Final velocity.