Universal Battery Charger Heat & Thermodynamics_Temperature & Heat and a 1-degree protractor

and a 1-degree protractor

and heart-tube formation for embryology and developmental biology teaching

letting students route current down either branch of a circuit by choosing which slot the plug occupies

providing a stable burner on classroom benches while controlling flame type through a collar

Hand-cranked pulley steps up to a smaller dynamo pulley through a rubber belt

Universal Battery Charger Heat & Thermodynamics_Temperature & Heat and a 1-degree protractorDesigned to recharge the cells used in laboratory apparatus, this universal charger keeps portable instruments running between sessions without rotating in fresh disposable batteries.