Dumbbell
device · 500 BC · Ancient world
A piece of exercise equipment.
What it is made of
- Dumbbell bar — has part. A steel rod that serves as a handle.
- Weight plates — has part. Weights.
- Dumbbell collars — has part. They secure the discs.
Principles and materials it uses
- Cast iron — is made of. Cast iron.
- Universal gravitation — uses. Weight.
- Stone — is made of. Greek halteres were stone dumbbells.