If you drop an ant or a pea sized model car off a building it won't even suffer any damage hitting the ground, if you throw an elephant or a full sized train of

If you drop an ant or a pea sized model car off a building it won't even suffer any damage hitting the ground, if you throw an elephant or a full sized train off a building, it will be pancaked or explode into pieces. The strength of a bone increases with its circumference, but its mass increases with its volume. The volume increases incur expenses in inertia far more quickly than circumference incurs gains in strength.