A ball is thrown straight upward and falls back to Earth. Suppose a y-coordinate axis points upward, and the release point is the origin. Instantaneously at the top its flight, which of these quantities are zero a. Displacment
b. Speed
c. Velocity
d. Accerlation

Which statements identify what astronomers currently know and think will happen with our universe? check all that apply. the big bang produced dark energy, which accounts for some of the energy needed to expand the universe. the vastness of space may contain a type of matter known as "dark matter." the universe is currently shrinking at a rapid rate. the universe is currently expanding at an accelerating rate. the big bang theory explains all the energy and matter discovered by scientists.

What would occur if the index of refraction of a material was less than n=1? the speed of light would increase to a speed larger than the maximum speed of light in a vacuum. the light wave would not bend at all though the material. the light wave would not be able to refract and would instead reflect off of the material. the speed of light would reduce to values close to 0 m/s.

What is the magnitude of the electric field at a point 0.0055 m from a 0.0025 c charge?