Question

Review Conceptual Example 6 as background for this problem. A car is traveling to the left, which is the negative direction. The direction of travel remains the same throughout this problem. The car's initial speed is 17.8 m/s, and during a 4.68-second interval, it changes to a final speed of (a)23.5 m/s and (b)15.3 m/s. In each case, find the acceleration (magnitude and algebraic sign).

Answer 1

Answer:

(a) 1.21 m/s² (b) 1.75 m/s²

Explanation:

The initial speed of the car, u = 17.8 m/s

Case 1.

Final speed of the car, v = 23.5 m/s

Time, t = 4.68-s

Acceleration = rate of change of velocity

$a=\dfrac{23.5 -17.8 }{4.68}\\\\a=1.21\ m/s^2$

Case 2.

Final speed of the car, v = 15.3 m/s

$a=\dfrac{23.5 -15.3}{4.68}\\\\a=1.75\ m/s^2$

Hence, this is the required solution.