Ascientist is giving a demonstration with a van de graaff generator in a class about electrostatics. the scientist can detect the type of charge on the van de graaff generator by
a) bringing a positively charged balloon near it.
b) seeing if it picks up bits of paper from a surface.
c) touching it with a metallic rod that conducts charge.
d) testing if it attracts a neutral sphere made of plastic.

A) bringing a positively charged balloon near it.

Explanation:

This is the correct answer because is the only option in which the object has a charge (a positive one in this case). That means when the scientist brings a positively charged balloon near the hollow metal globe on the top of the Van de Graaff generator a repulsion is seen it because the globe is positively charged too.

pe = weightxheight = 2000x1000=2,000,000joules

no. bullets are macro objects. wave nature is for light waves, extremely tiny particles. if a light particle was the size of your finger, the bullet would be the size of the universe. so basically, that huge difference in size makes the wave nature of matter insignificant.