Question

A car traveled at a constant velocity of 70 mph from noon to 2:00 pm. At 3:00 pm the velocity of the car was 80 mph; and finally at 4:30 pm the velocity of the car was 40 mph. Calculate the acceleration of the car between 3:00 and 4:30 pm. A) -40 mi hr2 B)-26.67 mi hr2 C)26.67 mi hr2 D) 40 mi hr2

Answer 1

Acceleration is the result when the difference in final and initial speed is divided by time. From the given, the acceleration from 3:00 to 4:30 pm is calculated through the steps below,
acceleration = (40mph - 80 mph) / 1.5 h
-26.67 mi/h²
Thus, the answer is letter B.