What is the magnitude of the electric field in which an electron experiences an electric force equal to its weight?

Force,F on electrons with charge ‘q” in electric field E.

Mass of an electron in weight m_E in gravity, and g = m_E*.

F=m_E*g is the minimum weight for electric force to equal its weight

This means that q*E is equal to m_E*g

Hence, E= m_E*g/q

m_E = 9.1×1031 Kg

g = 9.8m/s2

q = 1.6×10^-19 C

We get the numbers by putting in our numbers

E = 5.6×10-11V/m the required electric fields.