In April of 1869, he obtained a patent for one of his most important inventions, the air brake. This device enabled trains to be stopped with fail-safe accuracy by the locomotive engineer for the first time and was eventually adopted on the majority of the world's railroads
A good example of a centripetal force in political geography is: A powerful external threat.
Political geography can be defined as a subfield in geography that is focused on the study of boundaries, human government, divisions, and possessions of a nation, as well as outcomes of political processes in its states.
In Political geography, a centripetal force refers to the attitude that unifies the people living within a nation and it keep the nation together by stabilizing and strengthening it.
Basically, two good examples of a centripetal force in political geography are:
- A powerful external threat.
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