Fan and sailboat on wheels
• A+14+30
A sailboat and a fan are both independenly mounted on wheels with the sailboat in front of the fan. If the sailboat is held stationary while the fan is on the fan will move backwards. If the fan is held stationary and the sailbot allowed to move the sailboat will move forward. The two are then linked together and the class can be asked what direction the whole unit will go.
Related Demos
A+14+0 Weight on a vertical spring with markers on stand. A+14+1 Block pulled horizontally by a spring. A+14+5 Force table: Forces on a car on a horizontal table. A+14+10 Force table: Forces on a car on an adjustable inclined plane. A+14+15 Precision lever: Balance beam on stand plus weight set. A+14+16 A meterstick lever on a free-standing fulcrum with weights. A+14+17 Standard pan balance with assorted weights. A+14+20 Equivalence of tension of spring attached to pole with mass vs mass at both ends. A+14+21 Movable masses attached to rigid rod and force sensors A+14+25 Applet: Forces and Motion: Basics - Force, Motion, Friction A+14+26 Applet: Forces in 1 Dimension A+14+26 Applet: Forces Exerted on Bridges