Task 3.6
The voltage on the capacitor plates in the oscillatory circuit varies according to the law U = 10 cos 104t V.
The capacitance of the capacitor is 10 μF. Find the inductance of the circuit and the law of the change in the current in it.
Task 3.16
The equation of a plane wave propagating in an elastic medium has the form s = 10-8 sin (6280t - 1,256x :).
Determine the wavelength, the speed of its propagation and the frequency of oscillations.

PROBLEM 3.26
A light with a wavelength of 0.72 μm falls on a thin glass wedge. Distance between
The neighboring interference fringes are 0.8 mm in reflected light. Refractive index
Glass 1,5. Determine the angle between the wedge surfaces.
Task 3.36
Normally, light falls on the grating with a period of 6 μm. What spectral lines,
Corresponding to the wavelengths lying within the visible spectrum, will coincide in the direction
? = 30 °?

Task 3.46
The natural light passes through two polarizers, the angle between the principal planes of which is
thirty. How many times will the intensity of light decrease after passing this system? Think that
Each polarizer reflects and absorbs 10% of the incident light.
Task 3.56
In a Cerenkov counter filled with water, a beam of relativistic protons emits light in a cone with
Solution of 70 °. Determine the kinetic energy of protons.

Task 3.66
Determine the pressure of the sun's rays falling normally on the mirror surface. Intensity
Solar radiation is taken equal to 1.37 kW / m2.
Task 3.76
As a result of Compton scattering by a free electron, the wavelength of the gamma-photon increased
twice. Find the kinetic energy and momentum of the recoil electron if the scattering angle of the photon is
60 °. Before the collision, the electron rested.