A physicist drives through a stop light. When he is pulled over, he tells the police officer that the Doppler shift made the red light of wavelength 680 nm appear green to him, with a wavelength of 515 nm. The police officer writes out a traffic citation for speeding. How fast was the physicist traveling, according to his own testimony?

How do we measure or think of speed in the united states?

Abaseball is thrown from the outfield toward the catcher. when the ball reaches its highest point, which statement is true? (a)its velocity is not zero, but its acceleration is zero. (b) its velocity and its acceleration are both zero. (c) its velocity is perpendicular to its acceleration. (d) its acceleration depends on the angle at which the ball was thrown. (e) none of the above statements are true.

How do you know how many valence electrons an atom has?