Trundle wheel. This is used to measure approximate distances across large pieces of ground. The wheel has a circumference of one metre. It is pushed along the ground,so moves one metre for each revolution (assuming no slip). A device counts the number of revolutions and hence the distance covered. This is a simplified version of a surveyor's wheel | |
Licence : | Droits gérés |
Crédit: | Science Photo Library |
Taille de l’image : | 4308 px × 4308 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |