A physics demonstration compares two different waves: (1) a sound wave emitted by a tuning fork vibrating at 440 Hz that propagates through air, and (2) a monochromatic beam of visible electromagnetic radiation whose electric-field vector oscillates vertically as it travels horizontally toward a screen.
Answer all parts thoroughly; use clear, well-labeled sketches or diagrams where requested.
(a) Identify the type of mechanical wave produced by the tuning fork and state how the oscillations of the air molecules are oriented relative to the direction of wave propagation.
(b) Describe the orientation of the electric and magnetic fields in the electromagnetic beam relative to its direction of propagation.
(c) Suppose a rigid barrier with a single vertical slit of width much smaller than the sound wavelength is placed in the path of the sound wave. Explain why almost all of the sound still reaches a microphone placed behind the slit even though the opening blocks most of the geometric area.
(d) A second, identical vertical slit is now placed in the path of the electromagnetic beam. Qualitatively explain why the light transmitted through the slit remains detectable, whereas almost no light would be transmitted if the slit were rotated so that its long dimension were horizontal.
(e) Based on your explanations above, justify why sound cannot be polarized by passing it through a system of slits, whereas light can be polarized by such a system.