will the heavy jar or the light jar reach the bottom of the ramp first?

Which one starts first?

Wow, racing jars.  I've never heard of that before.  Racing cars maybe.

Try it yourself. Let an empty jar roll first, then fill with water and repeat

Aw, don't make it so simple in this electronic age.  Someone do the
calculations and then animate it for us, so that we can see it,
including a split-timing stopwatch that shows the time each jar
reaches the bottom of the ramp.
(I don't insist on good imaging, just moving jars and the stopwatch. :-)