Speedometer
part · 1888 · Electric age
A speed indicator (eddy-current type).
What it is made of
- Permanent magnet — has part. A rotating magnet drags the needle.
Principles and materials it uses
- Eddy currents — uses. An eddy-current speedometer.
- Brass — is made of. The housing is brass.
Where it is used
- Dashboard — is part of. A speedometer.
- Cruise control — is part of. It compares with the speed reading.