The discussion revolves around a physics problem involving electric charges, specifically a shell and a proton, and their kinetic and potential energies. The participants are analyzing the forces and energy transformations as the proton approaches the charged shell.
Some participants have provided calculations for the net charge and questioned the assumptions made about potential energy at the surface of the shell. There is a recognition of differing interpretations of the problem setup, particularly regarding the initial distance of the proton from the shell.
There are mentions of specific values for charges and constants, as well as the need to clarify the initial conditions of the problem, particularly the distance from which the proton approaches the shell.
The potential energy is key. The change in potential energy between the staring and ending locations will equal the magnitude of the change in kinetic energy of the particle. The potential for a charge q very near the surface of a spherical conductor with charge Q and radius r is kQq/r. The spherical charged surface behaves like a point charge located at its center.origamipro said:Q1 = 4E-16 Q2 = ?
q = 1.6E-19 qm = 1.67E-27
given answer Q2 = -3.96E-16
at the surface of the shell kinetic energy must equal zero. The potential energy at the surface does not need to be accounted for since it only wants value of Q2 when proton gets to the surface. Is this assumption correct, otherwise calculating E field at its surface becomes an approximation since the integral does not converge.
No need to integrate. Use conservation of energy via initial KE and change in PE for the two locations.so proton traveling in negative x direction, with two electric potentials both modeled from the same source point.
(1/2)m(v^2) -(q ∫ kQ1/r^2 ] 3R to R) + (q ∫ KQ2/r^2 ] 3R to R) = 0
(4.0915x10^-24) -2.74286E-24 + (1.6E-19)Q2(4.28571E10) = 0
solving for Q2 = -1.9667E-16