Why does a can of cranberry sauce roll so far? A can of
cranberry sauce rolls so far because it is thick and heavy.
There are two physical quantities of concern here: momentum and
angular momentum. When you push the can, you give it momentum.
By making the can roll, you also give it angular momentum. The
thickness of the sauce makes the cranberry sauce rotate with the
can itself. Both quantities are proportional to mass and speed.
The can stops after both momentum and angular momentum have been
removed. Because a rolling object does not slide along the
table, friction cannot take away the momentum or angular
momentum. Only air molecules can do this. The more mass and
velocity an object has, the more time is required for the
momentum to be drained. [A more extreme example is a bowling
ball vs. a balloon. If both are moving at the same speed, it is
much more difficult to stop the bowling ball because of its much
greater mass.] Click here to return to the Physics Archives
Update: June 2012