Electrical potential and Electrical Potential Energy Problems

Physics Ninja looks at 2 problems dealing with calculating the electrical potential and the potential energy in a charge configuration. In the 2nd problem an additional charge is released from rest and conservation of energy is used to find the speed of the charge when it is far away.

[jengel]

I love how you build off of each question in a progressively increasing difficulty. It makes my brain click for some reason. Thank you!!

[jadexpy]

The organic chemistry tutor has some competition

[whitwat]

This video is amazing! Studying for a bachelor's in Mech. Engineering, and your videos help so much. Thank you! New subscriber:)

[Bedouinlibya]

Thank you very much for your help, a follower from Libya

[nabob-tyough]

I honestly didn't think it would be this helpful. Thank you so much it was more than I expected!!

[noelomaolchraoibhe]

Master Physics Ninja-San, one of your grateful Grasshoppers needs HELP: what does an electric potential (EP) of nearly -12 MV at point P and a system-electric potential energy (EPE) of zero joules actually mean intuitively? In trying to internalize this content (thanks BTW, its brilliant) I reran the EP and EPE calculations but with 'P' at different locations and with the charges in various relative positions: I stuck with the single +q and two -q charges but positioned them equilaterally (one with 4 cm sides, another with 2 cm sides) and also placed them inline with q1 in the middle. I got system-EPE results that varied e.g., -2.5 MJ, -5.1 MJ, -3.4 MJ, -1.7 MJ, and -0.9 MJ. Calculating EP with P in different spots e.g., at the opposite end of a diamond shape extended from your original triangular configuration, gave me interesting results too e.g., -2.5 MV, -4.8 MV, -2.7 MV, and +3.5 MV when P is 1 cm from q1 and the three charges are about +64 MV when P is just 1 mm from q1 in the straight line configuration!
What prompted this was the "zero joules EPE" for the system in your original problem; I thought this implied "equilibrium" and that the charges would just 'float' in mutual repulsion & attraction until I realized that was nonsensical as the two -ve charges, left to their own devices, will inevitability move to oppose each other diametrically and then crash into the +ve charge, right? Beyond just solving the problems, it seems EP and EPE can be deceptive. Sorry about the verbose comment and THANKS for such great, thought-provoking content.
NB: for those passing by later who are too young to get the 'Grasshopper' reference, its from the 1972 pilot of the classic TV series "Kung Fu" (conceived by Bruce Lee but stolen from him by greedy Hollywood Execs!

[ea_tae]

How do we get the law V=k.. Q/r from this law V=k.E/Q