Which term is defined as the ratio of the speed of light in a vacuum to the speed of light in the material it is passing through? angle of incidence index of reflection index of refraction angle of reflection

When considering gravity acceleration and the force of acceleration, what must be true? a. the direction of acceleration must be perpendicular to the direction of the force. b. the direction of the force and the direction of acceleration must be the same as each other. c. the direction of the force and the direction of acceleration must be opposite of each other. d. the mass of the body must be the same as the acceleration of the body.

You win the lottery and decide to impress your friends by exhibiting a million-dollar cube of gold. at the time, gold is selling for $ 426.60 per troy ounce, and 1.0000 troy ounce equals 31.1035 g. -how tall would your million-dollar cube be? en cm

Lightning is an example of what phenomenon? a release of a large amount of energyan absorption of a large amount of energya natural electric circuita natural electric current