Question about net electric field between two charges

AI Thread Summary
The discussion centers on determining the direction of the net electric field at the midpoint between a positive charge +Q and a negative charge -Q. The consensus is that the net electric field points toward the negative charge, as the electric field from the positive charge at the midpoint is directed away from it. Participants emphasize the importance of visualizing electric field lines rather than focusing solely on the numerical values of the charges. The confusion arises from interpreting "net" in the context of electric fields rather than forces. Understanding the direction of the fields from both charges clarifies that they do not cancel each other out, leading to a net field toward the negative charge.
spencerchad
Messages
2
Reaction score
0

Homework Statement


A charge +Q exists at a point and directly west of this point a charge -Q exists. What is the direction of the net electric field at the midway point?

I'm studying old finals for my exam and this question keeps popping up in various forms. The answer is always directed toward the negative charge. To me the answer should be zero if say Q=1.0C.
 
Physics news on Phys.org
Ask yourself:
What's the direction of the field from the negative charge at the midpoint?
What's the direction of the field from the positive charge at the midpoint?
 
Draw a diagram and put in the directions of the electric fields of the 2 charges at the midway point.
Would these 2 fields add to zero?
 
Ah yes that make sense. I got hung up on "net" and thinking of the charges numerically rather than visualizing their electric field lines. Thanks for the quick reply!
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top