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.
When sound changes mediums (enters a different material) at an angle other that 90 degrees, it is bent from its original direction. This change in angle of direction is called refraction. Because of the angle, part of the wave enters the new medium first and changes speed.The difference in speeds causes the wave to bend. The velocity of sound in each material is determined by the material properties (elastic modulus and density) for that material.his change in angle of direction is called refraction. Because of the angle, part of the wave enters the new medium first and changes speed. The difference in speeds causes the wave to bend. The velocity of sound in each material is determined by the material properties (elastic modulus and density) for that material.