A stationary source emits a sound wave of frequency f, = 1.5kHz, intensity 7, = 0.5 and amplitude of relative pressure 4, = 12 Pa in a medium with modulus of elasticity B, = 250 x 10 ', but of impedance m acoustics Z, unknown. When the emitted wave enters an immobile substance of density p, = 8.1 and impedance Z,> Z, the wave transmitted in the substance has a sound intensity level I1, = 116.478 dB. a) Determine the values of Z, .Z, A and B ,? b) Determine the relative pressure wave function Ap, (x,) of the reflected wave if ø, = 0. c) What are the sound intensity levels of the incident wave and the reflected wave? d) If the source moves away from the substance and then perceives a beat frequency of 50.96 Hz, determine how fast the source is moving away from the substance. A layer of ice with refractive index n, = 1.31 and thickness e = 20cm has formed above of a body of water with index n = 1.33. A light source is located at a depth h = 3m below the ice cream. We want to determine the radius L of the circular region where the light passes through the interface. ice-water and the R-ray where it successfully crosses the ice-air interface. a) Calculate the radius L where the light passes at the water-ice interface. b) Determine the value of radius R. ) Is it possible that rays are trapped in the ice by multiple reflections between the 2 interfaces? air (n, -1) ice cream (n-1.31) water (n, = 1.33) water A thin biconcave lens, located in the air, of focal length | f | = 10 cm is located at Scm of a glass lens (n = 1.5) of thickness a = 10 cm of type concave-convex with the same radius of curvature R R RI = 10cm, the convex surface of which is covered with . mirror layer. If you place a real object 10 cm away left of the thin lens, determine the position and Mirror characteristics (type and magnification) of the image Dioptre ave final compared to the initial object. O-