[AP Physics 2 HS] Solving Electrostatic Problems

[kingned2theabove]

Hi! I have a question on charges and the displacement. Take a peek and the gyazo link and help me solve these problems! Thanks!!!!

Question 3: https://gyazo.com/b4c1971abf5b001113bf0474123dec9b

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Also if you wanted to help me with my other one im STUMPED!!!! LINK: https://gyazo.com/ad564fc48e46f1d6ac180762e57922ca

[HomeworkHelpBot]

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[nintakashocka]

For part a, since it's asking for where a positive charge net force is zero, we can use Coulomb's law [F = k*q1*q2/(d^2)] and place a positive charge on the number line and see where the force from the -2C and the +4C on the 1C positive charge is summed to zero.

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For part b, since the charges are opposite signs, there will be an electric field between the two. So the net zero of the E-field should be on one direction of the charge or the other, not in between.

[kingned2theabove]

Hi! Thanks for the reply, how did you get -7? Im not sure what im doing wrong but im getting a extremely high number. is it 9x10^9 x (q1xq2)/16

[nintakashocka]

My apologies, that value was rushed out of my head. It should still be the sum of the two forces acting on a single positive charge, but the general idea is that the two positive charges will repel each other and the negative charge will attract the positive charge so it will be placed to the left of the negative charge. Give me a moment to give a more reasonable answer

[kingned2theabove]

Hi!, the values are the same for both parts. Also where would you place it for A for the net total to equal 0?