There is a 85 uC point charge at the origin. What is the electric field at the point x= -45cm , y= 55cm. I am doing (-.45+.55)/(-.45^2+.55^2)^3/2
Where did I go wrong?
I have to find the elctric point for the Ex and Ey.
I understand where the (-.45^2+.55^2)^3/2 term comes from, but I don't see the Coulomb constant in your equation. In the numerator, you should have a vector with x and y components, but you are not using a vector notation. You need to show units also (preferably Coulombs and meters if you want the answer in Newtons/Coulomb)
To find the electric field at a given point, you need to use the equation:
E = k * Q / r^2
where:
- E is the electric field
- k is the electrostatic constant (approximately 9 × 10^9 N m^2 / C^2)
- Q is the magnitude of the point charge
- r is the distance from the point charge to the point where you want to calculate the electric field
In this case, the point charge has a magnitude of 85 μC (microcoulombs), which can be written as 85 × 10^-6 C. The point where you want to find the electric field has coordinates (x = -45 cm, y = 55 cm). To find the distance r, you can use the Pythagorean theorem:
r = sqrt(x^2 + y^2)
By substituting the values into the equation, we can calculate the electric field (both Ex and Ey):
r = sqrt((-45 cm)^2 + (55 cm)^2)
r ≈ 71.60 cm
E = (9 × 10^9 N m^2 / C^2) * (85 × 10^-6 C) / (71.60 cm)^2
To convert cm to meters, divide by 100:
E ≈ (9 × 10^9 N m^2 / C^2) * (85 × 10^-6 C) / (0.7160 m)^2
Now, by simplifying the equation, you can find the electric field at this point.