Axle
part · 3500 BC · Stone Age
A rod on which a wheel turns.
Principles and materials it uses
- Wood — is made of. The axle is wooden.
- Friction — uses. A wheel turns on its axle, overcoming friction.
Where it is used
- Wheel — is part of. A wheel turns on an axle.
- Cart — is part of. The wheels turn on an axle.
- Wheelset — is part of. A common axle.
- Car — is part of. A car's wheels sit on axles.
- Four-wheel drive — is used in. Four-wheel drive sends engine power to both axles, front and rear.
- Potter’s wheel — is part of. A vertical axis.
- Yo-yo — is part of. The axis between the discs.
- Armillary sphere — is part of. The celestial axis.