Do you like mysteries? Well, guess what, so did the physicists of the past! One of the greatest mysteries of the early 20th century was figuring out the charge to mass ratio of the electron. Let's dive in!

🚀 Big Picture Idea: Understanding how charged particles, like electrons, behave in a magnetic field helps us determine their properties.

• To determine the charge to mass ratio (often called 'specific charge') of a particle, measure how it moves in a magnetic field.
• Example: Electrons being fired through a gas (like hydrogen or helium). 🎈
• Why low pressure gas? So, our electron doesn’t bump into too many gas atoms and slow down too much.

Real-World Example: It's like trying to walk in an empty hallway (easy-peasy) vs. a crowded one (bump, excuse me, bump!)

• If a magnetic field is applied perpendicularly to the electron’s path, our electron dances in a circle! 🩰
• How do we see it? The electron excites gas atoms, which then emit visible light along its path.

Fun Fact: This is similar to how neon lights work. Electrons excite neon atoms which then glow!

• Electron's kinetic energy remains the same in the magnetic field (because the magnetic field and velocity are playing on different playgrounds, so no energy is taken or given).
• Energy is given by: ½ mev² = eV. It's a bit of math magic! 🎩✨