The particles that bounced back must have hit something incredibly small, dense, and positively charged (to repel the positive alpha particles).
This "spanking" of the old theory led to three massive conclusions that define modern chemistry:
Since most particles passed through, the atom wasn't a solid "pudding." rutherford spanking
Rutherford’s team set up a lead screen with a small hole to create a beam of (positively charged helium nuclei). They fired this beam at an incredibly thin sheet of gold foil.
Rutherford famously described the result by saying, "It was quite the most incredible event that has ever happened to me in my life. It was almost as incredible as if you fired a 15-inch shell at a piece of tissue paper and it came back and hit you." Why It Matters: The Birth of the Nucleus The particles that bounced back must have hit
Today, when students discuss "Rutherford spanking" the old guard of physics, they are referencing one of the most successful "gotcha" moments in scientific history—a moment where a simple piece of gold foil revealed the true nature of the universe.
While most particles passed through as expected, a small fraction did something shocking: Rutherford famously described the result by saying, "It
Rutherford proposed that electrons orbit this central "nucleus," much like planets orbit the sun. Legacy of the Rutherford Model
According to the Plum Pudding Model, the alpha particles should have passed straight through the "soft" positive charge of the gold atoms with very little deflection. The Result: A Scientific Shock