Potential from two charges

In summary, the problem involves two charges, one at the origin with a charge of -1.9 × 10-9 C and one on the x-axis at x = 3 m with a charge of 9.4 × 10-9 C. The question asks for the two locations on the x-axis where the potential is zero. To solve for this, the equation v=kq/x + (k(5Q/3-x)) is used, with xpositive = .5m and xnegative = m. However, there is confusion on how the electric field can be zero between two charges with opposite signs.
  • #1
zooboodoo
29
0

Homework Statement


A charge of -1.9 × 10-9 C is at the origin and a charge of 9.4 × 10-9 C is on the x-axis at x = 3 m. At what two locations on the x-axis (xpositive, xnegative) is the potential zero?
xpositive = m
Xpositive = .5m
v=kq/x + (k(5Q/3-x))to solve for this value,
.5

xnegative = m
I'm lost on the second part of the problem which we need to calculate the X negative
If someone could help me set this equation up I would be very appreciative :)


Homework Equations





The Attempt at a Solution

 
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  • #2
Careful.

How can the field be 0 on the line between a (+) and a (-) charge?
 
  • #3


To solve for the potential at any point on the x-axis, we can use the equation V=kq/x, where V is the potential, k is the Coulomb's constant, q is the charge, and x is the distance from the charge. In this case, we have two charges, so we need to consider the potential contributions from both charges at any given point on the x-axis.

At the origin, the potential is given by V = k(-1.9 × 10-9) / 0 = undefined. This is because the distance from the charge at the origin is 0, and we cannot divide by 0.

At x = 3m, the potential is given by V = k(9.4 × 10-9) / 3 = 3.13 × 10-9 V.

To find where the potential is zero, we can set up the equation V = 0 and solve for x.

0 = k(-1.9 × 10-9) / x + k(9.4 × 10-9) / (3-x)

Solving for x, we get x = 1.5m or x = 1.9m. These are the two locations on the x-axis where the potential is zero.

Therefore, xpositive = 1.5m and xnegative = 1.9m.
 

1. What is potential from two charges?

Potential from two charges refers to the electric potential energy that exists between two charged particles. It is a measure of the work required to move a unit charge from one point to another in the electric field created by the two charges.

2. How is the potential from two charges calculated?

The potential from two charges can be calculated using the formula V = kq/r, where V is the potential, k is the Coulomb's constant, q is the magnitude of the charges, and r is the distance between them.

3. What is the relationship between potential from two charges and distance?

The potential from two charges is inversely proportional to the distance between them. This means that as the distance between the charges increases, the potential decreases, and vice versa.

4. How does the sign of the charges affect the potential from two charges?

The sign of the charges determines the direction of the potential. If the charges have the same sign, the potential will be positive, indicating a repulsive force between the charges. If the charges have opposite signs, the potential will be negative, indicating an attractive force between the charges.

5. Can the potential from two charges be zero?

Yes, the potential from two charges can be zero if the charges have the same magnitude and opposite signs, and are placed at equal distances from a point in between them. This is known as a neutral point or equipotential point.

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