1) a) I placed several aluminum pie plates on top of the large metal sphere of the van de Graaff machine and then turned it on. After a few seconds the pie plates flew off. Explain why. Focus on physics involved.
b) When I placed packing peanuts in a pie plate they also flew off. Why? Can this be explained by the same physical mechanism as question a)? Explain.
c) A second smaller metal sphere was positioned nearby the van de Graaff machine. This sphere was grounded. Did this small sphere become charged? How and why? What was the interaction between the two spheres (attractive or repulsive)? Explain.