In the mousetrap simulation, which component represents the neutrons?

• A. Ping pong balls
• B. Mousetraps
• C. Boxes
• D. Tape

Answer: (A)

Ping pong balls stand in for neutrons in this hands‑on model. Neutrons are the moving particles that travel from one nucleus to another and cause fission when they collide with a nucleus, releasing more neutrons that keep the reaction going. In the mousetrap simulation, a ping pong ball moves around and, when it hits a mousetrap, the trap represents a nucleus undergoing fission and releasing additional neutrons (the ball), which can then hit other traps. The boxes are just positions or barriers for the atoms, and tape is simply used to set things up, not to represent particles. So the ping pong balls best embody the neutrons.