Coulomb's Law and Particle RepulsionDate: 09/26/2004 at 16:43:42 From: Carlos Subject: Calculate the force of repulsion between two electrons Two electrons are located 0.08 picometers from each other. Calculate the force of repulsion between them. I do not know the equation and do not know how to do this problem. Date: 09/28/2004 at 10:21:00 From: Doctor Ash Subject: Re: Calculate the force of repulsion between two electrons Hi Carlos. In order to solve this problem, you have to use Coulomb's Law: F = (K*q*q')/(d^2) where F is the force of attraction or repulsion q is the charge on the one particle q' is the charge on the other particle d is the distance between the charged particles K is a constant, approximately equal to 9*10^9 (N*m^2/C^2) Note that it doesn't matter which electron has charge q and which has charge q', since multiplication is commutative. The units should be as follows in order to comply with the unit of K: q and q' should be measured in C (Coulumbs) d should be measured in m (meters) F should be measured in N (Newtons) So, to solve the above question, first convert the units into the appropriate ones, i.e., 1 picometers (pm) = 10^-12 m Then substitute in the equation to find the magnitude of the electric force between the electrons. You now have K and d. What are q and q'? The charge on one electron is constant and is equal to -1.6 x 10^-19 C. Thus, q = q' = -1.6 x 10^-19 C Now you have all the values on the right side, so you can compute the force. The force will have a positive value showing that it is a repulsive force. (Attractive force is negative by convention). I hope this helps, and if you have any further questions, don't hesitate to ask. - Doctor Ash, The Math Forum http://mathforum.org/dr.math/ |
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