What is a centripetal force?
A centripetal force is a force or attitude that tends to unify people and enhance support for a state (p.239). They provide stability, strengthen the state, help bind people together, and create solidarity.

There are several examples of what a centripetal force in a state can be. Religion is a centripetal force in many states. For example, Hinduism in Nepal and India brings people together as they feel a sense of unity. Islam in Pakistan and Bangladesh, as well as Buddhism in Bhutan, is another example of religion as a centripetal force.

The term centripetal force comes from the Latin words centrum, meaning "center", and petere, meaning "tend towards" or "aim at". They are forces that unite and bind a country together - such as a strong national culture, shared ideological objectives, and a common faith.

Cultural homogeneity, national culture:France used to be a classic case of this, but immigration over the last 3 decades has changed this formerly white, Roman catholic, Francophone country, and produced serious centrifugal forces
A strong commitment to building a new nation; nationalism:Israel in 1948 - people with very different backgrounds, but desiring to create the state of Israel; helped by a common religion, and war
One religion can be an extremely strong centripetal force: Roman Catholicism (in Italy, in Mexico, in Brazil, in the Republic of Ireland) Hinduism in India Judaism in Israel Islam in several countries
One language is another strong unifier, since it is through language that culture is transmitted and acquired: Israel - the modern Hebrew language was created to unify people from many different countries who came to live in the new Jewish homeland USA - immigrants through the 19th century learned American English Indonesia - created a national language, Bahasa Indonesia, to unify a tremendously fragmented country
A powerful external threat can unite citizens: USA since 9.11.2001 USA during the Cold War - fear of Communism USSR during the Cold War - fear of "Capitalists" Citizens of the American Colonies united in opposition to British control in 18th century
A “charismatic” leader: Yugoslavia - Tito India - Mohandas Ghandi> Nehru> Indira Ghandi> Rajiv Ghandi; in combination with nationalism Germany 1930s - Adolf Hitler
Infrastructure: The transportation system in the US unites the people. The railroads in India unite the people.
Physical Geography: Pakistan is a good example for demonstrating how physical geography is a centripetal force. Pakistan as a river valley is isolated by mountains and deserts. These geographic features act as barriers that keep the people of Pakistan inside.
Language Language acts as a specific centripetal force because it unites people through a common form of communication. English in the U.S, Hindi in India, Bengali in Bangladesh, and Punjabi in Pakistan, eliminate miscommunication.
Transportation and Communication When there is good transportation in a state, there is easy access to all that is in the state. This makes life easier for people and helps reduce problems that would harm an easy-flowing society. Public transportation in the U.S and railroads in India are examples of this. Communication helps keep everyone in touch when it comes to important decision making. Having a good transportation/communication system helps to create a more dependable infrastructure for a country.
Nationalism Loyalty and devotion to a nationality helps to emphasize the common culture in a state through things such as mass media. It also promotes government, beliefs, and symbols (i.e. flags & songs). Communism once used symbols like the hammer and sickle to unite the people. The U.S has the national anthem, sung in schools and public events, to unite the state.
Compact State A compact state’s distance from the center to any boundary doesn’t vary greatly when it is a compact state. This makes internal communication easy in states such as Burundi, Rwanda and Poland; therefore it strengthens a country’s infrastructure. Compact shapes are beneficial to smaller states since it helps establish good communication in all regions.

What is a centrifugal force?
A centrifugal force is the exact opposite of a centripetal force. It is a force or attitude that tends to divide a state. Centrifugal forces lead to Balkanization (the process by which a state breaks down through conflicts among ethnicities—as threat to world peace, not just in a small area), as happened in the Balkans during WWI. Centrifugal forces are closely related not only to Balkanization, but also to devolution, which is also the breaking apart of a state. Centrifugal forces destabilize and weaken a state by disrupting the internal order of the state.

Just as centripetal forces were in abundance, centrifugal forces are as well. Many examples of centripetal forces can also apply to centrifugal forces because they are in different context within varying states. For example, the religion of Hinduism in India acts as a centripetal force, but in Pakistan it is a different situation. Religious Muslims groups of Shiite and Sunni, act as a centrifugal force because they fight amongst each other and break apart the state rather than unify it. Other examples of religion as a centrifugal force in a state include Islam and Hindu in India and Bangladesh, Buddhist and Hindu in Sri Lanka, Islam and Hindu in Kashmir, and Jains and Hindu in India.

The term centrifugal force comes from the Latin words centrum, meaning "center"’ and fugere, meaning "to flee". They are forces that divide a country - such as internal religious, linguistic, ethnic or ideological differences.

Different religious beliefs can be the dominant centrifugal force in a country:Muslims and Hindus in India
Different languages can also be important causes of unrest : Canada - Francophones, especially in Quebec, will not be satisfied till they have a totally independent country.
Cultural diversity - in some countries important differences in several aspects of culture create powerful divisions and centrifugal forces: the former Yugoslavia - shattered into 5 separate countries and probably more to come typified diversity in culture, with Serbs, Croats, and Muslims the main groups Sri Lanka - Hindu Tamils wage terror against the Sinhalese Buddhists
Irredentism - an external country may seek to expand its territory by appealing to peoples of the same culture living as a minority in a nearby country: Pakistan and Afghanistan - the Pushtun/ Pathan China and Xizang Tibet "Turkestan" - the Uzbeks Iran-the Azeri
Physical Geography: Just like physical features, such as mountains and rivers, can unify a country. They can also separate a country. Mountains divide communities in Nepal.
Language There are over 2,000 languages spoken in the African continent alone, with as many as 8,000 dialects. This acts as a centrifugal force because it creates a rupture in communication. Conflicts can easily begin due to a lack of communication.
Ethnic groups There are at least 2 million ethnic and tribal groups in African States. Each group has differing sets of cultural styles of living and beliefs. Not having the same beliefs is a way to easily break up states. Conflicts begin and wars occur. This difference in lifestyles is a major step away from further developing a country, especially if they are in a stage 1 or stage 2 of the demographic transition.
Multinational State If a state has 2 or more ethnic groups that are aiming for self determination, this can be considered a centrifugal force. States that want self determination are not united and they wish to separate and form their own country. This is an exact model of a centrifugal force and its result can be seen in what was Yugoslavia. The conflicting ethnic groups caused world wars and eventually broke up into several countries. Former Soviet Union is also an example of a multinational state that experienced the effects of centrifugal forces. It broke up into 15 independent countries
Physical Boundary Physical boundaries, like mountains and bodies of water, cause an obvious split within states. Mountains in Nepal cause a separation among communities in the state. There is great difficulty in communicating and traveling between communities which further exemplifies the breaking apart of a state.