Why do not the negatively charged electrons fall into the positively charged nucleus?

Identify the positively charged sol.

Who determined the charge on the electrons ?

When a body becomes negatively charged. Its mass.

When negatively charged colloids like As_(2)S_(3) sol is added to positively charged Fe(OH)_(3) sol in suitable amounts :

how do histones acquire positive charge ?

Why does an ebonite rod get negatively charged on rubbing with fur?

Is it possible to have a positively charged body at

Which of the following is a positively charged sol ?