Can someone please answer this question along with the strategy they used to ans
ID: 1422494 • Letter: C
Question
Can someone please answer this question along with the strategy they used to answer it? I want to know how to go about solving this kind of problem.
Map sapling learning Four point charges are arranged as shown below, each a distance d from the center of the configuration. The value of the constant q is positive. Let blue arrows represent electric fields and red arrows represent forces. For each charge, pick the picture that best represents the directions of both the electric field at the charge and the net force on the charge due to the other three charges. 3.0 1.0q 1.0q -3.0qExplanation / Answer
The Answers are,
Top Charge = Red Arrow Down , Blue Arrow Up.
Bottom Charge = Red Arrow Up , Blue Arrow Down.
Left Charge = Red Arrow Right , Blue Arrow Right.
Right Charge = Red Arrow Left , Blue Arrow Left.
Strategy is nothing just you need to find Net Magnitude of Electric Field for each charge.
So Let's say in 1st case on the top most -3q charge,
Electric Field due to bottom charge will be = k*3q/(4*d^2) = 0.75 * k*q/d^2 Vertically Down.
Electric Field due to two Left & Right charge will be =2*K*q/(2*d^2) * cos(45) = 0.707 k*q/d^2 Vertically Up.
P.S = The X components of Electric field due to left & right charge will cancel each other out and thus there will only be vertical compnent of field.
Net Field = 0.75 * k*q/d^2 - 0.707 k*q/d^2
Net Field = 0.043 k*q/d^2 Vertically Down
Now As Electric Field is down & charge is negative, Therefore Force on charge will be opposite of the direction of Electrci field i.e Vertically Up.
SO that's how we get this done, You can practice the others yourself :)