DandelionTheory Posted October 6, 2020 Posted October 6, 2020 (edited) So 2 like charges are traveling along an electric field, the same direction, with force FExx spaced next to each other. If the electrostatic force between them is greater than FExx, the resulting force on each charge would be greater than 45° from FExx right? I'm looking to use the electrostatic force between charges to "bounce off the surface" of a cone. (picture) FE1 and FE2 are the forces between respective charges and the electric field, while FC Represents the electrostatic force between both charges. Edited October 6, 2020 by DandelionTheory
DandelionTheory Posted October 6, 2020 Author Posted October 6, 2020 using the coulomb force as thrust is hard...
swansont Posted October 6, 2020 Posted October 6, 2020 You haven’t shown the electric field. I assume it’s in the -x direction. The force on a charge will be the vector sum of FE and FC On 10/6/2020 at 3:56 AM, DandelionTheory said: using the coulomb force as thrust is hard... Expand Ion drives do exist already
DandelionTheory Posted October 7, 2020 Author Posted October 7, 2020 (edited) On 10/6/2020 at 10:47 AM, swansont said: Ion drives do exist already Expand Ion drives do not harvest beam drift for additional thrust as a primary design point. If FC is larger than FE the side of the cone will be a shorter distance from the charge than the center. Edited October 7, 2020 by DandelionTheory
DandelionTheory Posted October 7, 2020 Author Posted October 7, 2020 (edited) The plus and minus indicate electric field direction. If FE was alternating, so the charge wiggles in the Y-+ direction, they would contact the angled sides of the cone with each cycle due to FC. Edited October 7, 2020 by DandelionTheory
swansont Posted October 7, 2020 Posted October 7, 2020 On 10/7/2020 at 4:36 AM, DandelionTheory said: Ion drives do not harvest beam drift for additional thrust as a primary design point. Expand Perhaps no, but then, I made no claims about that. On 10/7/2020 at 4:36 AM, DandelionTheory said: If FC is larger than FE the side of the cone will be a shorter distance from the charge than the center. Expand Can you show this mathematically? It's not obvious why this would be true. FE has no dependence on distance, and FC does not depend on the distance to the side of the cone. Seems to me if the distance to the cone could be made arbitrarily large and have no effect on the forces. On 10/7/2020 at 7:15 AM, DandelionTheory said: The plus and minus indicate electric field direction. Expand Plus being the direction a negative charge would travel?
DandelionTheory Posted October 7, 2020 Author Posted October 7, 2020 (edited) On 10/7/2020 at 10:24 AM, swansont said: Can you show this mathematically? Expand I can do my best, although i do need help. Vectors are shown in the Magnitude(x, y) form. if the force on a charge in an electric field is: FE = qE where E is the electric field vector and q is the charge I messed up earlier and drew the picture with the electrodes labeled as their charge(q) and not their electric potential(battery poles). the force between 2 like charges can be shown: |FC| = K(Q1Q2/r2) where K is the Electrostatic Constant (9.0x109 Nm2 /C2 ), Q1= charge 1 Q2= charge 2 r = the distance between charges so if the electric field vector is FE = 1(0, -1), the coulomb force on charge 1 from charge 2 is FQ1 = 2(1, 0), the coulomb force on charge 2 from charge 1 is FQ2 = 2(-1, 0), and Ftotal = FE + FC a vector calculator shows me Ftotal for Q1 = 2.23(2, -1) which is 333.43 degrees, and Ftotal for Q2 = 2.23(-2, -1) which is 206.57 degrees if the electric field was an alternating, FE would cause each charge to change direction in the +-Y direction and FC would force the charges away from each other in the +-X direction. so i'm assuming due to the angle of the side of the cone, with every half cycle the charges would come into contact with it and reflect off; always moving from the center and always alternating their Y position with the AC cycle. i changed the photo Edited October 7, 2020 by DandelionTheory
swansont Posted October 7, 2020 Posted October 7, 2020 On 10/7/2020 at 3:28 PM, DandelionTheory said: so if the electric field vector is FE = 1(0, -1), Expand If? What if it's stronger than that? Or weaker? 19 minutes ago, DandelionTheory said: the coulomb force on charge 1 from charge 2 is FQ1 = 2(1, 0), the coulomb force on charge 2 from charge 1 is FQ2 = 2(-1, 0), and Expand The distance between the charges is not given. What does an amplitude of 2 even mean? 19 minutes ago, DandelionTheory said: Ftotal = FE + FC a vector calculator shows me Ftotal for Q1 = 2.23(2, -1) which is 333.43 degrees, and Ftotal for Q2 = 2.23(-2, -1) which is 206.57 degrees Expand Why are these different angles with respect to the x axis? Your diagram looks like it has mirror symmetry along the center line. This answer can't possibly be right, according to the information you have provided. 19 minutes ago, DandelionTheory said: if the electric field was an alternating, FE would cause each charge to change direction in the +-Y direction and FC would force the charges away from each other in the +-X direction. so i'm assuming due to the angle of the side of the cone, with every half cycle the charges would come into contact with it and reflect off; always moving from the center and always alternating their Y position with the AC cycle. Expand This is assuming information that you did not provide. You didn't specify the electric field or the position of the charges, or the distance to the cone. When you make a claim absent such detail, the claim is held to be true in general. And true in general means you can show it without putting numbers in for any of the variables.
DandelionTheory Posted October 7, 2020 Author Posted October 7, 2020 (edited) On 10/7/2020 at 4:00 PM, swansont said: The distance between the charges is not given. Expand On 10/6/2020 at 2:51 AM, DandelionTheory said: spaced next to each other. Expand On 10/7/2020 at 4:00 PM, swansont said: What does an amplitude of 2 even mean? Expand |FC| = K(Q1Q2/r2) K = 9.0x109 Nm2 /C2 r = 0.001m Q1 = 1.5x10-8C Q2 = 1.5x10-8C gives 2.02N On 10/7/2020 at 4:00 PM, swansont said: You didn't specify the electric field Expand On 10/7/2020 at 3:28 PM, DandelionTheory said: so if the electric field vector is FE = 1(0, -1), Expand On 10/7/2020 at 4:00 PM, swansont said: or the distance to the cone. Expand true. the distance isn't important until the electric field is alternated, i should have specified that. it makes little sense for the charge to initially hit the side of the cone with the first half of the AC cycle, it seems more probable the charge would collide with a side during the other half of the cycle On 10/7/2020 at 4:00 PM, swansont said: When you make a claim absent such detail, the claim is held to be true in general. And true in general means you can show it without putting numbers in for any of the variables. Expand thank you, ill keep that in mind. did i miss anything? Edited October 7, 2020 by DandelionTheory
DandelionTheory Posted October 7, 2020 Author Posted October 7, 2020 (edited) On 10/7/2020 at 4:00 PM, swansont said: Why are these different angles with respect to the x axis Expand Coulomb force between the 2 charges is on the x axis, the electric field experienced by the 2 charges is on the y. In my head it was easier to visualize, is there a preferred method? Edited October 7, 2020 by DandelionTheory
swansont Posted October 7, 2020 Posted October 7, 2020 On 10/7/2020 at 4:59 PM, DandelionTheory said: |FC| = K(Q1Q2/r2) K = 9.0x109 Nm2 /C2 r = 0.001m Q1 = 1.5x10-8C Q2 = 1.5x10-8C gives 2.02N Expand You didn’t specify this value of r until after you made your claim. Your diagram says the charge is 1C Are you admitting your claim is incorrect, seeing as you have to fudge the numbers to make things work?
DandelionTheory Posted October 8, 2020 Author Posted October 8, 2020 (edited) On 10/7/2020 at 9:22 PM, swansont said: You didn’t specify this value of r until after you made your claim. Expand "Next to each other" isn't hard to grasp. On 10/7/2020 at 9:22 PM, swansont said: Your diagram says the charge is 1C Expand Yes and there was is no electric field vector either according to you. But.... Yeah I mentioned them. I explained with an if statement when things are changed for argument sake. No AC in the diagram either, yet it's part of the design.... Interesting. On 10/7/2020 at 9:22 PM, swansont said: Are you admitting your claim is incorrect, Expand Is that before you don't understand my claim or after you assume I'm confused? On 10/7/2020 at 9:22 PM, swansont said: seeing as you have to fudge the numbers to make things work? Expand On 10/7/2020 at 4:00 PM, swansont said: What does an amplitude of 2 even mean? Expand Seems like you forgot what "if" means... Reading comprehension is important in physics... Edited October 8, 2020 by DandelionTheory -1
swansont Posted October 8, 2020 Posted October 8, 2020 On 10/8/2020 at 2:23 AM, DandelionTheory said: "Next to each other" isn't hard to grasp. Expand It’s not quantitative
DandelionTheory Posted October 8, 2020 Author Posted October 8, 2020 On 10/8/2020 at 2:41 PM, swansont said: It’s not quantitative Expand Neither is your respect. "Oh gatekeeper, find another that can understand the passwords so I may enter your citadel. Oh swansonnet gatekeeper of understanding." Is that better?
swansont Posted October 8, 2020 Posted October 8, 2020 On 10/8/2020 at 6:55 PM, DandelionTheory said: Neither is your respect. "Oh gatekeeper, find another that can understand the passwords so I may enter your citadel. Oh swansonnet gatekeeper of understanding." Is that better? Expand No, actually, it’s pathetic.
DandelionTheory Posted October 8, 2020 Author Posted October 8, 2020 Yeah. Sharing ideas isn't something that can be done with you. Why do you reply? Why does trolling the forums so important when you cannot comprehend a description of 2 force vectors? No for get this I'm done. Have fun gatekeeping, nobody will entertain your thoughts if you cannot entertain theirs.
swansont Posted October 8, 2020 Posted October 8, 2020 On 10/8/2020 at 10:00 PM, DandelionTheory said: Yeah. Sharing ideas isn't something that can be done with you. Why do you reply? Expand I was trying to answer your question, but your problem was ill-posed, and somehow now it’s now my fault that you didn’t quantify multiple variables, made up numbers after the fact, and made an assertion that you can’t back up. 16 minutes ago, DandelionTheory said: Why does trolling the forums so important when you cannot comprehend a description of 2 force vectors? No for get this I'm done. Have fun gatekeeping, nobody will entertain your thoughts if you cannot entertain theirs. Expand I know that force vectors have a magnitude that can’t be calculated if you don’t have the information to do the calculations. Something you have not shown you understand.
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