Marvin & Milo
What you need:
Walking toy or object that will slide
About 50 cm of string
A small lightweight bag
Paper clips and binder clips
Fix a rubber band round the object and tie the string to it.
Put it on a smooth table and attach a small bag to the end weighted down with paperclips and binder clips to make a small weight.
With the object about 30 cm from the table edge, try out different weights until it will start to slide if you give it a gentle push.
Results & explanation
When you push the object, it will slide till it reaches the edge of the table, then stop. If you're using a walking toy, it should stop walking at the edge.
The force on the toy from the weight acts sideways and downwards, so the string is pulled diagonally, but only the sideways part of it keeps the toy moving forward. As it nears the table edge, the angle of the string changes until there is no part of the force moving the toy forward, so it stops. Some walking toys come with a weight attached, which is why they stop.
See previous cartoons
Free fall ride
See more on physics.org