"Federalist No. 47 is the forty-seventh paper from The Federalist Papers. It was published on January 30, 1788 under the pseudonym Publius, the name under which all The Federalist Papers were published. James Madison was its actual author. This paper examines the separation of powers among the executive, legislative, and judicial branches of government under the proposed United States Constitution due to the confusion of the concept at the citizen level. It is titled "The Particular Structure of the New Government and the Distribution of Power Among Its Different Parts"." - Wikipedia
Inequalities between the Third Estate and the other two estates, as well as hunger and poverty, led the Third Estate to attack the nobles and demand a new constitution.
One big thing the Constitution changed about the Articles was giving the central government more power to actually rule the country. This relates for the governments need for power and support in order to operate properly.