What constitutional principle is a Country's constitution adhering to when it's branches of government remain independent of each other?

The constitution instituted three branches of government: the executive, the legislature, the judiciary. Separation of powers is popular sovereignty, or the jurisdiction of the people's rule is the principle that the authority of a state and it is the government is created and supported by the constant of its people, through their chosen representatives.

This is the source of its political power. The people have an absolute say in government decisions. Popular sovereignty assumes the existence of some form of popular consent. It can also be described as the voice of the people.

Separation of powers.-the idea of separation of powers was set forth by montesquieu during the age of enlightenment as a means of providing a system of checks and balances in government to prevent tyrannical rule. montesquieu believed that by separating the roles and responsibilities of government into separate branches, society could create a system where each branch could check each others power in order to create a better balance of power. the responsibilities of government that montesquieu wanted separated were the law-making branch (i.e., legislative), the law-executing branch (i.e., executive), and the law-interpreting/judging branch (i.e., judicial).