Lesson 1 - Electric Field
Full playlist: • Campo elétrico
In this video, I present the definition of electric force as a function of the electric field and initial concepts.
Examples:
1) A test charge q = +2nC is placed at a point P at a distance d from a charge Q = – 8 mC. If the charge q is subjected to a force of 4000 N, what is the intensity of the electric field at point P?
2) At a point in an electric field, the electric field vector has a vertical direction, pointing downwards, and an intensity equal to 5.10³ N/C. A small sphere weighing 2.10⁻³ N and charged with an unknown charge is placed at this point. Knowing that the small sphere remains in equilibrium, determine:
a) the intensity, direction, and sense of the electric force acting on the charge;
b) the value of the charge.
3) An electric pendulum has a length L = 1.0 m. The suspended sphere has a mass m = 10 g and an electric charge q. In the region where the pendulum is located, the acceleration due to gravity is 10 m/s², and there is an electric field whose vector E is horizontal and has a magnitude of 7.5 x 10³ N/C. The pendulum comes to a stop with the sphere at a distance d = 0.60 m from the vertical line dropped from the suspension point. Determine the charge q.