Bat Weight/Exit Speed Question

[Intheboondocks]

The initial question was about the weight (the physics of which hasn't changed to my knowledge), now if the -10 and the -9 have different moments of inertia that will also impact exit speed, bat manufacturers don't generally publish that information other than to say "end loaded" or "balanced".

Dr. Russell also has nice write ups on swing weight (MOI) and the sweet spot (center of percussion and bending modes).