Task 2.7
If the center of the square, at the vertices of which are charges of +2 nC, put a negative
Charge, the resultant force acting on each charge will be zero. Compute the numeric
The value of the negative charge.

Task 2.17
What kind of work do the forces of the field do if the charges of the same name 1 and 2 nC, located at a distance of 1
Cm, dispersed to a distance of 10 cm?
Task 2.27
Find the volumetric energy density of the electric field produced by a charged metal
Sphere of radius 5 cm at a distance of 5 cm from its surface, if the surface charge density on it
2 μC / m2.

Task 2.37
Determine the electromotive force of the battery, the short-circuit current of which is 10 A,
If a resistor with a resistance of 2 Ω is connected to it, the current in the circuit is 1 A.

Task 2.47
An infinitely long rectilinear conductor with a current of 3 A is located at a distance of 20 cm from the center
Coil with a radius of 10 cm with a current of 1 A. Determine the intensity and induction of the magnetic field in the center
Turn for cases where the conductor:
A) is located perpendicular to the plane of the turn
B) in the plane of the revolution

Task 2.57
At a distance of 5 mm parallel to the rectilinear long conductor, an electron moves with
Kinetic energy of 1 keV. What force will act on the electron, if a current of 1 A is applied to the wire?
Task 2.67
Solve problem 66 for the case of a solenoid with a core whose magnetic permeability is 1000.

Task 2.77
A conductor with a current of 1 A, 0.3 m long, rotates uniformly about an axis passing through its end in
Plane perpendicular to the lines of induction of a magnetic field of intensity 1 kA / m. For one
Minute of rotation, the work is 0.1 J. Determine the angular velocity of rotation of the conductor.