The type of armor (in this case, I don't mean the material, but whether it is a helmet, chestplate, leggings, or boots) helps determine the number of armor points that the equipped armor adds. Is the armor type also taken into account in determining how effective an enchantment is?
For example, say you have Blast Protection IV on a pair of boots; will that enchantment negate more damage from explosions if instead placed on a chestplate?