1.Platforma as a disc of radius 1 m rotates by inertia, making 6 rev / min. On the edge of the platform is a person whose mass is 80 kg. Weight of platform 200 kg. How many revolutions per minute will make the platform, if a person goes into its center? The moment of inertia person should be calculated as the moment of inertia of the material point.
2.1 kmol gas being at a temperature T1 = 300 K, cooled isochorically, in consequence of which the pressure is reduced by half. The gas then expands isobarically so that in the final state, its temperature is equal to the original. Show process diagram P, V. Find the entropy increment S, the increment of internal energy U, do the work of A.
3.Tochechnye charges Q1 = 20 SCLC and SCLC Q2 = -10 are at a distance d = 5 cm apart. To determine the field strength at a point remote to r1 = 3 cm from the first and r2 = 4 cm from the second charge. Identify and force F, acting at this point to a point charge Q = 1 SCLC.
4.Elektron with a kinetic energy of 5 eV, flew in a uniform electric field in the direction of the field lines. What speed will have an electron passing in this field is the potential difference in the two?
5.Plosky capacitor has an insulating layer of a glass plate having a thickness d = 2 mm and S = area of \u200b\u200b300 cm2. The capacitor is charged to the potential difference U = 100 V, and then disconnected from the voltage source. Define the work to be performed in order to remove the glass plate of the capacitor (friction is not taken into account). The dielectric constant glass = 7.
6.Proton and -particle moving at the same speed, fly into the parallel plate capacitor plates. How many times is the deviation of the proton field capacitor will be larger deviations -particles.
7.EDS Battery 6 V. With the closure of it to an external resistance of 1 ohm it gives a current of 3 A. What is the current short-circuit of the battery?
8.Skolko parallel light bulbs, designed for 100 V and a power consumption of 50 watts each, can burn at full heat of their power from the battery to the EMF equal to 120 V and an internal resistance r = 10 ohms?
9.Tok 20A goes down a long straight conductor, bent at right angles. Find the magnetic field strength at a point lying on the bisector of this angle and spaced from the vertex at a distance of 10 cm.
10.Elektron moving in a uniform magnetic field with the induction of T along a helical path with a radius of 1 cm and 7.8 cm step. Determine the orbital period of the electron and its speed
11.Kvadratny contour of side = 20 cm, in which flows a current of 5 = A, located in a magnetic field with induction of B = 0.5 T = 30 angle to the lines of induction. What kind of work you need to commit to at a constant current of the circuit change its shape to square a circle?
12. In a uniform magnetic field strength H = 2000 A / m, uniformly with frequency n = 10 cm long rod is rotated so that its plane of rotation perpendicular to the lines of tension, and the axis of rotation passing through one of its ends. To determine the potential difference at the ends of the rod.
13.Solenoid comprises N = 800 turns. When the current strength and the magnetic flux F = 0,1mVb. Determine the energy of the magnetic field of the solenoid. The core is made of non-magnetic material and the magnetic field is uniform in the whole volume.