Equilateral Triangle Point Charge Forces

• xortan
In summary, the problem involves three identical point charges, Q, placed at the vertices of an equilateral triangle with side length d. The task is to find the magnitude and direction of the total electrostatic force on the charge at the top of the triangle using the formula F= kqQ/r^2. After initial attempts, the key realization is that the potential formula should be replaced with the force formula and the angles should be taken into account.
xortan

Homework Statement

Three identical point charges, Q, are placed at the vertices of an equilateral triangle as shown in the figure. The length of each side of the triangle is d. Determine the magnitude and direction of the total electrostatic force on the charge at the top of the triangle

F= kqQ/r2

The Attempt at a Solution

I have attached a picture of the problem, I've attempted the problem a few times now and I am getting no where near the answer cause I seem to be working in circles as I just get them canceling each other off...Can someone push me in the right direction I got a midterm on this stuff in a couple days

Edit: After I posted this I went back to the question. Since it is an equilateral I know that all the angels must be 60 degrees. I split the triangle down the middle so i had 2 right angel triangles. So would it be (sin60 kQ/r) + (sin60 kQ/r)? I am still pretty confused..

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Hi xortan,

xortan said:

Homework Statement

Three identical point charges, Q, are placed at the vertices of an equilateral triangle as shown in the figure. The length of each side of the triangle is d. Determine the magnitude and direction of the total electrostatic force on the charge at the top of the triangle

F= kqQ/r2

The Attempt at a Solution

I have attached a picture of the problem, I've attempted the problem a few times now and I am getting no where near the answer cause I seem to be working in circles as I just get them canceling each other off...Can someone push me in the right direction I got a midterm on this stuff in a couple days

Edit: After I posted this I went back to the question. Since it is an equilateral I know that all the angels must be 60 degrees. I split the triangle down the middle so i had 2 right angel triangles. So would it be (sin60 kQ/r) + (sin60 kQ/r)?

That is along the right idea; however kQ/r is the formula for the potential of a point charge, and here they want the force between two point charges (based on the formula you provided for F). So retry writing it using your force formula.

I am still pretty confused..

1. What is the difference between trigonometry and electrostatics?

Trigonometry is a branch of mathematics that deals with the relationships between angles and sides of triangles, while electrostatics is a branch of physics that studies electric charges at rest and their interactions.

2. How are trigonometric functions used in electrostatics?

Trigonometric functions, such as sine, cosine, and tangent, are used to determine the direction and magnitude of electric fields and forces in electrostatics problems.

3. Can trigonometry be used to solve electrostatics problems?

Yes, trigonometry can be used to solve electrostatics problems by using the relationships between angles and sides of triangles to determine the direction and magnitude of electric fields and forces.

4. What is Coulomb's law?

Coulomb's law is a fundamental law in electrostatics that describes the force between two electrically charged particles. It states that the force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.

5. How is the concept of electric potential related to trigonometry?

The concept of electric potential in electrostatics can be visualized as a scalar field. Trigonometry is used to determine the potential at a point in this field by calculating the distance and direction from the point to the source of the electric field.

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