Acar travels down a highway at 25 m/s. an observer stands 150 m from the highway.
(a) how fast is the distance from the observer to the car increasing when the car passes in front of the observer?
explain your answer without making any calculations.
(b) how fast is the distance increasing 20 s later?

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.

Ain is , is 's of ? 0.62 0.79 1.27 1.50

Ascientist notices that an oil slick floating on water when viewed from above has many different colors reflecting off the surface, making it look rainbow-like (an effect known as iridescence). she aims a spectrometer at a particular spot and measures the wavelength to be 750 nm (in air). the index of refraction of water is 1.3