"Electricity and magnetics"

Purpose
A set of laboratory equipment to carry out laboratory physical practicum in the course of «Electricity and magnetics» includes 8 laboratory facilities and methodology. The eight laboratory facilities are designed in the same style and include a microprocessor unit which enables to carry out analog-digital conversion of currents and voltages output signals in the studied samples which are shown on graphical and symbol displays. The output of data can be manual and in case of necessity they may be printed. The information exchange with a PC is possible when a slight modification is done.
Characteristics
The set includes 8 laboratory facilities and methodology:

	Ohm's law for alternating current circuits The facility enables to check Ohm's law in alternating current circuits for seven different loads. The graphical display introduces the diagrams of dependence of instantaneous currents and voltages within the range of one period. The amplitude value of voltage can be measured discretely with the step of 0.5 V within the range from 0 to 5 V. Actual and instantaneous voltages and currents as well as a phase shift between current and voltage are directly measured with the relative error < 1 %.
	Power and phase shift in alternating current circuits The facility makes it possible to study conversion of electrical energy in alternating current circuits for several different loads. The graphical display introduces diagrams of dependence of instantaneous current and voltage within the range of one period. The amplitude value of voltage can be measured discretely with a step of 0.5 V in the range from 0 to 5 V. Actual and instantaneous currents and voltages as well as a phase shift between current and voltage with relative error making < 1 % are directly measured values.
	Dependence of metals and semiconductors resistance on temperature The facility is designed to check the law of measurement of two metals (copper, platinum) resistance and two doped semiconductors (germanium, silicon) resistance from temperature. The interval of temperature change makes 20-100 0Ñ. The graphical display simultaneously builds four diagrams of dependency of resistance from temperature. Relative error for temperature and resistance measurement is < 1 %.
	Study of magnetic hysteresis The facility makes it possible to study the magnetic properties of three various materials (soft iron, iron and ferromagnetic). The graphical display builds the corresponding hysteresis loops, in accordance with which the dependence of magnetic permeability of the studied sample from magnetic induction value is established.
	Electric resonance The facility makes it possible to study resonance in series and parallel oscillation circuits with various values of the parameters R, L and C (by 5 for each). The graphical display builds resonance curves which can be studied in the manner we did in previous works. The frequency measurement range makes 0 - 645 Hz with discreteness 10 Hz
	Study of relaxation processes The facility makes it possible to study relaxation oscillations in oscillation circuit, condenser charging and discharging and relaxation generator operation.
	Determination of induction of solenoid magnetic field The facility makes it possible to study solenoid magnetic field distribution on its axis and to stay Hall effect. The derived experimental dependency is compared to theoretical dependency calculated by solenoid geometrical dimensions.
	Study of quadripoles properties The facility makes it possible to study the properties of four types of filters: low and high frequencies filters and band-transmission and band-stop filters, as well as resonance amplifier. The graphical display builds amplitude and frequency and phase-and-frequency characteristics.