Persona 3 Reload: Which tool did Foucault use in his experiments?

On the afternoon of May 13 (5/13) in Persona 3 Reload, you’ll have a physics lesson with Mr. Takenozuka. During a discussion of the Earth’s rotation, he’ll ask you which tool the French physicist Léon Foucault used in his experiments. It’s a hard question.

Léon Foucault rose to fame in 1851 after demonstrating the effect of the Earth’s rotation in spectacular fashion at the Panthéon in Paris. He wasn’t the first scientist to make such a demonstration, but he was the first to grab the public’s attention, and the tool he used ended up being named after him.

Did Léon Foucault use the hourglass, the pendulum, or the planisphere in his experiments?

After explaining the Earth completes one full rotation every 24 hours and introducing Léon Foucault as a groundbreaking figure, Mr. Takenozuka picks on you and asks which tool he used in his experiments. Now you have to choose from the following answers:

• The hourglass
• The pendulum
• The planisphere

Well, I confess I didn’t know the answer to this one off the top of my head, but compared to some of the other school answers in Persona 3 Reload, it was fairly easy to find out. As it says on the Léon Foucault Wikipedia page, he was most famous for his demonstration of the Foucault pendulum. So, the answer is “The Pendulum.” Say that Léon Foucault used the pendulum in his experiments, and you’ll get a little boost to your Charm social stat.

Although this type of pendulum ended up being named after Foucault, he didn’t actually invent it. That honor goes to the Italian Vincenzo Viviani, who performed much the same experiment two centuries earlier but crucially did not make the connection to the Earth’s rotation.

Which of the following did Léon Foucault use in his experiment on the rotation of the Earth?

Your favorite French physicist, Foucault, comes up again in the midterm exams. Specifically, in the physics exam on May 20 (5/20). This time, the question is worded a little differently, and you’re given different answers to choose from:

• A magnet
• A tuning fork
• A pendulum
• A vacuum tube

It’s basically the exact same question, though, and it has the same answer: A pendulum. Léon Foucault used a pendulum in his experiment on the rotation of the Earth. It was really more of a demonstration than an experiment, but I’m going to let that slide because life’s too short to spend time picking holes in Persona 3 Reload’s notions of reality.