Category Archives: Electrical
This project is similar to the 4WD car, not only in that the student is working with wood and electrics, but also that the concept of drive ratios is involved. The crane takes this a little further: one can observe how the winch diameter affects lifting speed and power, and the very useful principle of mechanical advantage gained by the two pulleys. When this is taught in schools, it is normally not easy for kids to really get it as a concept; how the addition of pulleys increases the lifting power and reduces the speed. More often than not they only wind up memorizing formulas so they can pass the test and forget about it. But by making and playing with one themselves, they can see first-hand what actually happens when you add pulleys. They no longer need to memorize anything – they just know it.
This is also a lot of fun to play with. Continue reading
A galvanometer is a device for measuring the flow of an electric current. (From Galvani, a professor of physiology at Bologna, and meter, measure.)
In this day and age, electricity has found its way into our lives in the most unexpected areas. Nobody could have imagined how useful computers and cellphones would become, but how far can it go? I thought electric toothbrushes were pushing the limit once, but then I saw a computer controlled toilet seat….. Continue reading