1. The problem statement, all variables and given/known data K i need help with like 3 phyics problem on electric forces / charges. 1. One gram of copper has 9.48 10^21 atoms, and each copper atom has 29 electrons. (a) How many electrons are contained in 1.08 g of copper? _________ electrons b. What is the total charge of these electrons? __________ C 2. Calculate the net charge on a substance consisting of a combination of 7.5 10^13 protons and 4.2 10^13 electrons. ___________ C 3. An alpha particle (charge = +2.0e) is sent at high speed toward a gold nucleus (charge = +79e). What is the electric force acting on the alpha particle when the alpha particle is 4.8 10^-14 m from the gold nucleus? _______________ N 2. Relevant equations Elctron -1.6 x 10^-19 Proton: 1.6 x 10^-19 Coulombs Law: Felectric = Kc (q1*q2)/r^2 3. The attempt at a solution alright iv been having trouble since our teacher did not teach us anything about these barley and the book doesnt help at all. 1st one i dont know where to start. 2nd one i tried just simply adding them together and that didnt work and then i tried using pythagorm theorm because iwas maybe thinking that the net force you need to find like the triange. 3rd one i plugged into the columbs law and i got 6.2x10^38 and i think i got that wrong too? Any help please?