Both sides previous revision Previous revision Next revision | Previous revision |
184_notes:pc_energy [2021/05/19 13:57] – schram45 | 184_notes:pc_energy [2024/01/22 22:26] (current) – [Deriving Electric Potential Energy for Two Point Charges] tdeyoung |
---|
[{{ 184_notes:twocharges.png?300|Two charges are initially separated by ri. After some time they are separated by rf.}}] | [{{ 184_notes:twocharges.png?300|Two charges are initially separated by ri. After some time they are separated by rf.}}] |
| |
Using the relationship between force and potential energy, we can derive the electric potential energy between two point charges from the electric force. Suppose we have two positive point charges q1 and q2, who are initially separated by a distance r. We will //__assume q1 is fixed__// and let q2 move to infinity. Starting with the general relationship: | Using the relationship between force and potential energy, we can derive the electric potential energy between two point charges from the electric force. Suppose we have two positive point charges q1 and q2, who are initially separated by a distance r. We will //__assume __//q1//__ is fixed__// and let q2 move to infinity. Starting with the general relationship: |
ΔUelec=Uf−Ui=−∫fi→Felec∙d→r
| ΔUelec=Uf−Ui=−∫fi→Felec∙d→r
|
we can plug in the electric force equation for the force from q1 on q2 (point charges), and we know that our initial location is ri=r and our final location is rf=∞. So we get: | we can plug in the electric force equation for the force from q1 on q2 (point charges), and we know that our initial location is ri=r and our final location is rf=∞. So we get: |
| |
====Examples==== | ====Examples==== |
Video Example: | * [[:184_notes:examples:Week3_particle_in_field|Particle Acceleration through an Electric Field]] |
| * Video Example: Particle Acceleration through an Electric Field |
| * [[:184_notes:examples:Week3_spaceship_asteroid|Preventing an Asteroid Collision]] |
| * Video Example: Preventing an Asteroid Collision |
{{youtube>_rghROIzNUk?large}} | {{youtube>_rghROIzNUk?large}} |
Written out work: [[:184_notes:examples:Week3_particle_in_field|Particle Acceleration through an Electric Field]] | |
| |
Video Example: | |
{{youtube>vf_b6k3iXeU?large}} | {{youtube>vf_b6k3iXeU?large}} |
Written out work: [[:184_notes:examples:Week3_spaceship_asteroid|Preventing an Asteroid Collision]] | |