Uniform circular motion: wall of death

Rhett "Rotten" Giordano, New Orleans Superdome Bike Expo
http://www.650motorcycles.com/83expoGrinder.jpg

Demonstration of how the (upwards) static friction force prevents the bike from sliding down the "Wall of Death," while the (inwards pointing) normal force provides the net force required for uniform circular motion.

Uniform circular motion: centripetal net force

Li Wei, liweiart.com
047-01, "Life in the high I" (detail)
Beijing July 1, 2004

Demonstration of the inward (centripetal) net force required for uniform circular motion.