Question

Charged comb attract pieces of paper, but a charged battery doesn't, why?

Answer 1

Basically, when an electrification takes place, electrons are not created but they are transferred and the comb gets electrically charged. In the case of comb attracting tiny bits of papers when rubbed with dry hair is because electrons from the dry hair get transferred to the comb and now the comb induces a dipole in the bits of paper and the paper gets attracted. In the case of battery, the sum of net charge present in the positive and negative terminal of the battery is zero. So the net outside electric field is zero.