1D40.71-Awkward Rollers | ![1d4071_awkward_rollers](https://websites.umass.edu/plecprep/files/2015/07/1d4071_awkward_rollers-300x225.jpg) | The diameter of the circular wheel is equal to the radii of the three arcs that make up the awkwardly-shaped ... |
1D50.10-Ball on String | ![1d5010_ball_on_string](https://websites.umass.edu/plecprep/files/2015/07/1d5010_ball_on_string-300x225.jpg) | A simple ball on a string to show uniform circular motion wherein the centripetal force is provided ... |
1D50.20-Centripetal Force Apparatus | ![1d5020_centripetal_force_apparatus](https://websites.umass.edu/plecprep/files/2015/07/1d5020_centripetal_force_apparatus-300x225.jpg) | This demonstration illustrates centripetal force. For equilibrium, the centripetal force must ... |
1D50.40-Pail of Water | ![1d5040_pail_of_water_2](https://websites.umass.edu/plecprep/files/2015/07/1d5040_pail_of_water_2-300x225.jpg) | As a bucket or cup of water is spun in a circle, the water does not fall out. This is because the string .. |
1D60.10-Howitzer and Bridge | ![1d6010_howitzer_and_bridge](https://websites.umass.edu/plecprep/files/2015/07/1d6010_howitzer_and_bridge-300x225.jpg) | This demonstration shows that the horizontal motion of a projectile undergoes no acceleration. Push the ... |
1D60.20-Drop and Shoot | ![1d6020_two_ball_drop_2](https://websites.umass.edu/plecprep/files/2015/07/1d6020_two_ball_drop_2-300x225.jpg) | This demonstration illustrates that a ball shot out horizontally and a ball dropped with zero initial ... |
1D60.30-Monkey Hunter | ![1d6030monkey_hunter](https://websites.umass.edu/plecprep/files/2015/07/1d6030monkey_hunter-300x225.jpg) | If a hunter aims his gun at the monkey, and the monkey lets go the instant the hunter fires, will the ... |