Which of the following is an example of acceleration? select one: a. a boy walks two miles in one hour. b. a girl walks two miles per hour north for three hours. c. a boy walks two meters north, turns west, and walks another two meters. d. a girl drives a total distance of 240 miles in just under four hours.

Glass is transparent to visibile light under normal conditions; however, at extremely high intensities, glass will absorb most of the light incident upon it. this works through a process known as multiphoton absorption. in this process, several photons are absorbed at the same time. if very intense light whose photons carry 2ev of energy is shined onto a material with a band gap of 4ev, that light can be absorbed through two-photon absorption, because two photons have the right amount of energy to bridge the band gap. what is the minimum number of photons of 800-nm light that are needed to equal or exceed the band gap of fused silica glass

Alead ball is dropped into a lake from a diving board 5m above the water . it hits the water with a certain velocity and then sink with constant velocity in bottom . it reaches the bottom 5 second after it is dropped if g= 10m/s2 . find depth of the lake and average velocity of the ball ?

The diagram shows four locations in the electric field of a positive point charge m. at which location is the electric potential the greatest.