a) Biot’s Apparatus :- Comprising of a brass sphere N.P. and two removable hemisphere with insulated handles mounted on insulated stand on tripod or round base. b) Biot’s Apparatus :- Same as above but with 10 cm Size dia.
Van-De-Graff Generator :- All improved version over whimshirt machine showing its filled effect from a longer distance Collecting sphere is removable to show the construction details. Fitted on wooden base with hand rotation wheel and connection in earth new design.