PIRA: 1D60.20

Summary of the Demo

Two balls undergo vertical free fall, one with an initial horizontal velocity, yet both land simultaneously.  

Equipment List

  • Ring Stand
  • Pira # 1D60.20 (Box)
    • Simultaneous Fall Apparatus
    • Bubble Level(If not attached.)
    • Solid Steel Ball
    • Steel Ball with a hole through it

Simultaneous fall demo

Set-up Instructions

Time required:~5 minutes


  • Attach Apparatus to ring stand
  • Level the apparatus

Demonstration instructions

Time required:~2 minutes


  • Cock Spring (after leveling)
  • Place Solid Steel Ball on indentation
  • Place remaining ball on the other end with rod through it
  •  Release spring