Fresnel and Fraunhofer diffraction. Fresnel diffraction is produced when light from a point source meets an obstacle, the waves are spherical and the pattern observed is a fringed image of the object. Fraunhofer diffraction occurs with plane wave-fronts with the object effectively at infinity. The pattern is in a particular direction and is a fringed image of the source.
The statement “When
an object is in orbit, it is falling at the same rate at which the Earth is
curving” is true. The speed of a satellite orbiting the earth depends only on
the mass of the earth and the mass of the satellite.
