Question

If I were a guy in the 17th century, what would I use as a foundation to assert the presence of something difficult to observe, such as electromagnetic waves? What specific, easy experiment would demonstrate their existence?

Answer 1

In the 17th century, the understanding of electricity and magnetism was still in its early stages, and the existence of electromagnetic waves was not known. However, there were some precursors and early experiments that laid the foundation for the discovery of electromagnetic waves in the 19th century.

One experiment that could have provided some evidence for the presence of something difficult to observe, like electromagnetic waves, is the phenomenon of static electricity and electrostatics. This experiment could be conducted using simple tools available during that time, such as an amber rod or a glass rod rubbed with silk.

The experiment could proceed as follows:

1. Rubbing: Rub an amber rod or a glass rod with silk. This action transfers electric charge onto the rod, causing it to become electrically charged.

2. Attraction and Repulsion: Bring the charged rod close to lightweight objects, such as small pieces of paper or hair. Observing the attraction of the objects towards the rod or their repulsion can demonstrate the presence of an invisible force.

3. Replication: Encourage others to perform the same experiment with different materials, such as rubbing amber with fur or glass with wool. Consistent observations of attraction or repulsion would support the idea of a common phenomenon.

This experiment helps establish the existence of electrical charges and the force they exert on other objects. While it doesn't directly prove the existence of electromagnetic waves, it lays the groundwork for understanding electricity and paves the way for future investigations into the nature of electromagnetic phenomena.

It's important to note that the discovery of electromagnetic waves and their properties, including their existence and the ability to propagate through space, was achieved through the pioneering work of scientists like James Clerk Maxwell and Heinrich Hertz in the 19th century. Their experiments and mathematical formulations of electromagnetism led to the development of a comprehensive theory of electromagnetic waves.