Refraction is a phenomenon which results when a ray of light enters from one medium to another medium. When a ray of light enters from denser medium to rarer medium, it bends away from the normal. The laws of refraction are: The incident ray, the refracted ray and the normal all lie in the same plane.
Answer:
(1) The orbits are ellipses, with focal points ƒ1 and ƒ2 for the first planet and ƒ1 and ƒ3 for the second planet. The Sun is placed in focal point ƒ1.
(2) The two shaded sectors A1 and A2 have the same surface area and the time for planet 1 to cover segment A1 is equal to the time to cover segment A2.
(3) The total orbit times for planet 1 and planet 2 have a ratio a13/2 : a23/2
Answer:
freqiency=velocity/wavelength
ief=20/2000=0.01hz