What is the the electric field at a point midway between

In summary, the electric field at a point midway between a -7.39 uC and a +5.17 uC charge 3.32 cm apart, taking the direction towards the positive charge to be positive, is 1.014E8 N/C. When calculating the electric field, the distance between the charges should be divided by 2, and the value for r should be squared.
  • #1
shimizua
100
0

Homework Statement


What is the the electric field at a point midway between a -7.39 uC and a +5.17 uC charge 3.32 cm apart? Take the direction towards the positive charge to be positive.


Homework Equations


E1=kq1/r^2
E2=kq2//r^2
E1+E2=Etotal


The Attempt at a Solution


E1=8.9E9(5.17E-6)/.0332^2
E2=8.9E9(-7.39E-6)/.0332^2
I got 4.1E7 and 5.97E7 which i added up for 1.014E8 N/C
 
Physics news on Phys.org
  • #2
Are you sure you didn't make a sign error for E2?
Also, the charges are 3.32 cm apart. You are situated midway through them. How could then r be 3.32 cm?
 
  • #3
wow thanks, i didnt even think about how it was in the middle. thanks again so much
 
  • #4
I'm working on this problem also, and getting something wrong. I'm using the same equation as you. Did you find that dividing r/2 gave you the correct answer?
 
  • #5
um...ya. so i just divided the r by 2. but u still have to make sure you are squaring it? post up ur numbers and stuff and what you get if you are still having trouble and ill see if i can help you out
 
  • #6
What is the the electric field at a point midway between a -7.79 uC and a +5.66 uC charge 3.74 cm apart? Take the direction towards the positive charge to be positive.

So I did:

(9E9)(-7.79E-6)/(.00187^2)

and

(9E9)(5.66E-6)/(.00187^2)

then added the two answers together, which isn't working.
 
  • #7
sorry it took so long, i had a class. it would be .0187 not .00187. that is probably why. does that work now?
 

1. What is the electric field at a point midway between two point charges?

The electric field at a point midway between two point charges is equal to the sum of the electric fields created by each individual charge. This can be calculated using the formula E = kQ/r^2, where k is the Coulomb's constant, Q is the charge of the point charge, and r is the distance between the point charge and the midpoint.

2. How do you determine the direction of the electric field at a point midway between two point charges?

The direction of the electric field at a point midway between two point charges is determined by the direction of the individual electric fields created by each point charge. The direction of the electric field is always directed away from a positively charged point charge and towards a negatively charged point charge.

3. Can the electric field at a point midway between two point charges be zero?

Yes, it is possible for the electric field at a point midway between two point charges to be zero. This occurs when the individual electric fields created by each point charge are equal in magnitude but opposite in direction, resulting in a cancelation of the electric field.

4. How does the distance between the two point charges affect the electric field at a point midway between?

The electric field at a point midway between two point charges is inversely proportional to the square of the distance between the charges. This means that as the distance between the charges increases, the electric field at the midpoint decreases.

5. Can the electric field at a point midway between two point charges be negative?

Yes, the electric field at a point midway between two point charges can be negative. This occurs when the individual electric fields created by each point charge are in opposite directions and have different magnitudes, resulting in a net negative electric field at the midpoint.

Similar threads

  • Introductory Physics Homework Help
Replies
10
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
5
Views
730
  • Introductory Physics Homework Help
Replies
6
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
3K
  • Introductory Physics Homework Help
Replies
3
Views
814
  • Introductory Physics Homework Help
Replies
3
Views
4K
  • Introductory Physics Homework Help
Replies
3
Views
683
Back
Top