I think the crumpled paper because it has more weight
Answer:
Net charge produce due to presence of different chargers in the vicinity or in the considered region.
Explanation:
Net electric charge is just a concept introduce to identify the result of the presence of number of charges which interact with each other. It can be found by treating electric chargers in algebraic form like numbers, where +charges get added with +charges
-charges get added with -charges
and when adding two charges with opposite signs they get subtracted and the symbol of the resultant charge comes from the charge with highest magnitude.
Water vapour and a drop in temperature to condense water vapour into a cloud. Something to see the cloud also, such as "pollution" particles.
Since in an electromagnetic wave the electric and magnetic fields are perpendicular to each other and perpendicular to the direction of motion, the electric field has to point in the z direction.