Two electrostatic point charges of +53.0 µC and +44.0 µC exert a repulsive force on each other of 166 N. What is the distance between the two charges? The value of the Coulomb constant is 8.98755 × 109 N · m2 /C 2 . Answer in units of m

The energy equivalent of the rest mass of an electron is

Which is a substance that can be separated by physical means and is not the same throughout

The illuminance of a surface varies inversely with the square of its distance from the light source. if the illuminance of a surface is 120 lumens per square meter when its distance from a certain light source is 6 meters, by how many meters should the distance of the surface from the source be increased to reduce its illuminance to 30 lumens per square meter?