# 3 Q Electric Field: Point Charges, Ring, Sphere, Gauss,

I am really having trouble understanding the concepts of these problems because I have found the median of each side of the triangle to find the center then using geometry i was able to figure out the angles but i am completely lost on what to do next! Please can some one explain to me how to do this problem!

1)Three electric insulated point charges are forming an equilateral triangle with side a.

a.) Find electric field at the center of this triangle.

b.) What will be the magnetic field at the center of the same triangle, when charges are moving along its sides with constant velocity v in clockwise direction and are exactly in the middle between two consequent corners?

2) A metal ring of radius r carries uniformly distributed along its circumference charge Q. Define the electric field in the center of this ring and on its axis (assume that the distance form some point on the axis to the center of the ring is a).

3) A solid, insulating sphere of radius (a) has a uniform charge density p and a total charge +Q. Find the magnitude of the electric fiel in the regions r<a and r>a. Draw the schematic graph of electric field ( E vs. r).

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1) Three electric insulated point charges are forming an equilateral triangle with side a.

a.) Find electric field at the center of this triangle.

b.) What will be the magnetic field at the center of the same triangle, when charges are moving along its sides with constant velocity v in clockwise direction and are exactly in the middle between two consequent corners?

2) A metal ring of radius r carries uniformely distributed along its circimference charge Q. Define the electric field in the center of this ring and on its axis (assume that the distance form some point on the axis to the center of the ring is a).

3) A solid, insulating sphere of radius (a) has a uniform charge density p and a total charge +Q. Find the magnitude of the electric fiel in the regions ra. Draw the schematic graph of electric field ( E vs. r).

Reading:

Electric field

In physics, an electric field or E-field is an effect produced by an electric charge (or a time-varying magnetic field) that exerts a force on charged objects in the field. The SI units of the electric field are Newton per coulomb. Electric fields exist around all charges; the direction of field lines at a point is defined by the direction of the electric force exerted on a positive test charge placed at that point. The strength of the field is defined by the ratio of the electric force on a charge at a point to the magnitude of the charge placed at that point.

The electric field or electric field intensity is a vector quantity, and the electric field strength is the magnitude of this vector.

The mathematical definition of the electric field is developed as follows. ...

#### Solution Summary

The expert examines electric fields for point charges, ring, spheres and Gauss. The center of triangles in electric field are determined.