Guinness World Records 2013 Honorees Include Tallest Cat, Tallest Dog And Tallest Donkey. This is a bittersweet time for Debby Maraspini. The 2013 edition of Guinness World Records just came out and her beloved cat, Savannah Islands Trouble -- Trouble for short -- is in the book as the tallest cat ever, with a height of 19 inches.
Refraction is the change in direction of waves that occurs when waves travel from one medium to another. Refraction is always accompanied by a wavelength and speed change. Diffraction is the bending of waves around obstacles and openings. The amount of diffraction increases with increasing wavelength.
The refraction is the change of the sound direction on passing from one medium to another. In ultrasound, refraction is due to sound velocity mismatches combined with oblique angles of incidence, most commonly with convex scanheads.