Quick Answer: The Centre of Percussion apparatus is a cradle that fixes to the test frame and suspends a fixed metal rod pendulum with a heavy sphere beside a wooden compound pendulum. Students use it to locate the centre of percussion of the wooden pendulum.
Last updated: October 2026
Key Features
Cradle mounts on the test frame and suspends both pendulums
Metal rod pendulum with a heavy sphere supplies the percussion force
Wooden (compound) pendulum absorbs the impact, like a bat held underhand
Hardened steel knife edges on a smooth cradle surface let the wooden pendulum pivot freely
Visible horizontal movement at the pivot shows any reaction
Technical Specifications
Specification
Value
Mounting
Cradle fixed to the test frame
Striking pendulum
Fixed metal rod with heavy sphere
Impact pendulum
Wooden compound pendulum
Pivot
Hardened steel knife edges on a smooth surface
About This Product
Students first find the centre of gravity of the wooden pendulum and use it to calculate its radius of gyration and centre of percussion. They then swing the metal sphere into the wooden pendulum at points above, below and at the centre of percussion and note the reaction each time. The set-up mirrors a ball striking a bat.
Frequently Asked Questions
What do students measure with the Centre of Percussion apparatus?
They find the centre of gravity of the wooden compound pendulum, calculate its radius of gyration and centre of percussion, then check the reaction when the metal sphere strikes above, below and at that point.
