A race car completes the final lap of a race on a 2-kilometer circular track. At the start of the lap, it crosses the line at 60 meters/second. It completes the lap 28.57 seconds later, crossing the line at 85 meters/second. Calculate the displacement and average acceleration of the car within the span of 12 seconds.

Respuesta :

Answer: A 
A. Displacement is 0 meters, and acceleration is 0.88 meters/second2. 
B. Displacement is 2,000 meters, and acceleration is 1.14 meters/second2. 
C. Displacement is 0 meters, and acceleration is 70.0 meters/second2. 
D. Displacement is 2,000 meters, and acceleration is 80.0 meters/second2. 
E. Displacement is 0 meters, and acceleration is 0.70 meters/second2.

-Displacement is change in position in a specified time interval. Since the initial and the final positions are equal, the displacement is zero. 
-Average acceleration is change in velocity over change in time. Hence, the average acceleration is (85 m/s - 60 m/s)/28.57 s = 0.88 m/s^2

Answer:

A. Displacement is 0 meters, and acceleration is 0.88 meters/second2.

Explanation: