If a clean, positively charged zinc plate is exposed to intense white light it will not discharge. If a clean, negatively charged zinc plate is exposed to intense white light it will not discharge.

Remarkably, the group also discovered that, depending on the solvent, the impact varies for positively and negatively charged ...

In 1919 Rutherford had discovered the proton, a positively charged particle within the atom's ... their positive charge was canceled out by the negatively charged electrons. So in the helium ...