A man who weighs 75kg on the surface of the earth whose mass is 6*10^24kg. If the radius of earth is 6480km ,calculate the force of attraction between them. A man who weighs 75kg on the surface of the earth whose mass is 6*10^24kg. If the radius of earth is 6480km ,calculate the force of attraction between them.

Four point charges each having charge q are located at the corners of a square having sides of length a. find symbolic expressions for the following. (a) the total electric potential at the center of the square due to the four charges (use any variable or symbol stated above along with the following as necessary: ke.) vtotal= (b) the work required to bring a fifth charge p from infinity to the center of the square (use any variable or symbol stated above along with the following as necessary: w=