College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

Exercise 71

A car accelerates horizontally from rest on a level road at a constant acceleration of 3.00 m/s 2. Down the road, it passes through two photocells ("electric eyes" designated by 1 for the first one and 2 for the second one) that are separated by 20.0 m. The time interval to travel this 20.0-m distance as measured by the electric eyes is 1.40 s. (a) Calculate the speed of the car as it passes each electric eye. (b) How far is it from the start to the first electric eye (c) How long did it take the car to get to the first electric eye