Prokofiev VL - the solution of the entire version 08 on

Prokofiev VL - the solution of the entire version 08 on

Task 2.8
Charges of 1 nC are placed at the vertices of an equilateral one; Triangle with a side of 0.2 m.
Equal force acting on the fourth charge placed on the middle of one side
Triangle is 0.6 μN. Determine this charge of the strength and potential of the field at its point
Location.

Task 2.18
At a speed of 2 • 107 m / s, the electron flies into the space between the plates of the flat capacitor in
Middle of the gap in the direction parallel to the plates. At what minimum potential difference
On the plates, the electron does not fly out of 1 capacitor, if the length of the capacitor is 10 cm, and the distance between
Its lining is 1 cm?
Task 2.28
The plate area of ​​a flat mica condenser is 1.1 cm2, the gap between them is 3 mm. At discharge
Condenser, an energy of 1 μJ was released. To what potential difference was the capacitor charged?

Task 2.38
The electromotive force of the car battery is 12 V. With a current strength of 3 A, its efficiency is 0.8.
Determine the internal resistance of the battery.

Task 2.48
With a square frame with a side of 0.2 m, a current of 4 A flows. Determine the intensity and induction of the magnetic
Field in the center of the frame.

Task 2.58
The proton moves in a magnetic field of intensity 10 A / m along a circle with a radius of 2 cm. Find
Kinetic energy of the proton.
Task 2.68
The current in the solenoid rises uniformly from 0 to 10 A per 1 min, while the solenoid accumulates
Energy 20 J. Which EMF is induced in the solenoid?

Task 2.78
A homogeneous magnetic field, whose volume energy density is 0.4 J / m3, acts on the conductor,
Located perpendicularly to the lines of induction, with a force of 0.1 mN per 1 cm of its length. Determine the strength
Current in the conductor.