Examination of the audio signatures and normal modes of vibrations of US Mint Pennies and Dimes

Examination of the audio signatures and normal modes of vibrations of US Mint Pennies and Dimes

What I am Doing

Modes of vibration of circular plates

First round of Data

Penny drops 1 and 3

Dime drop 1 and 3

Penny drop 3 and dime drop 3

Problems with First Round of Data

Dropping Mechanism

Rotation due to Torque

Second Round of Data

Adjustment to Dropping Mechanism

Third Round of Data

Investigation of Lower Frequencies

Ball Bearing Drops 1 - 4

Fourth Round of data

Coin Compositions

2003 dime vs 1954 dime

1991 Penny vs 1953 Penny

1954 Dime vs 1953 Penny

Poisson’s Ratio

Expected Frequencies

Expected Frequencies cont.

Testing the human ear

Acknowledgements