UC Berkeley Logo Catalog

Object rolls uphill, center of mass rolls downhill

• A+5+21

diagram for demo

In this demonstration a solid object is able to roll uphill. This is accomplished by the widening of the track such that the center of mass of the object is sinking while it’s supports on the railings are rising.

Related Demos


  1. UCB
  2. A+5
  3. Conservation of Energy
A+5+0 Ball on string mounts on blackboard and pivots on lower rod. A+5+5 The Trebuchet A+5+10 Equal path lengths ball race. A+5+15 Brachistochrone: Three balls falling along different trajectories. A+5+20 Bowling ball pendulum swings back to nose. A+5+22 Potential energy of spring imparted to ball on ramp A+5+25 Film loop: "Conservation of energy: Pole vault", 3:55 min. A+5+26 Java applet: Conservation of energy skate park, movable tracks A+5+27 Java Applet: Conservation of energy skate park, various graphical representations A+5+28 Java Applet: Racing balls along different tracks A+5+29 Java Applet: "Mass-spring oscillator with optional energy graphs"
UC Berkeley Physics
Demonstration Database and Scheduling System
Copyright © 2026 UC Regents; all rights reserved