Final answer:
In 1820, Orsted made the initial observation that an electric current creates a magnetic field.
Step-by-step explanation:
In 1820, Hans Christian Orsted made the initial observation that there is a relationship between electricity and magnetism. He discovered that an electric current flowing through a wire creates a magnetic field around it.
This observation became known as the electromagnetic effect and laid the foundation for the field of electromagnetism. Orsted's findings were crucial in the development of technologies such as electric motors and generators.
Today, we understand that when an electric current passes through a conductor, it generates a magnetic field perpendicular to the direction of the current. This relationship between electricity and magnetism is described by Ampere's Law and is a fundamental principle in physics.
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