Question

Approximately what is the total stopping distance, in feet, if the car is traveling at a speed of 40 miles per hour when the driver is signaled to stop?

• A. 130
• B. 110
• C. 90
• D. 80
• E. 70

Hint:

For stopping distance problems, always add the distance traveled during reaction time to the braking distance obtained from the graph.

Answer 1

The Correct Option is A

Step 1: Recall total stopping distance formula.
The total stopping distance is the sum of: \[ \text{Distance during reaction time} + \text{Distance after brakes are applied}. \] Step 2: Find distance during reaction time.
From the first graph (Distance vs Speed during reaction time), at 40 mph, the distance is approximately 40 feet.
Step 3: Find distance after brakes are applied.
From the second graph (Distance after brakes), at 40 mph, the distance is about 88 feet.
Step 4: Add both distances.
\[ \text{Total distance} = 40 + 88 = 128 \approx 130. \] Step 5: Conclusion.
Thus, the total stopping distance is approximately: \[ \boxed{\text{(A) 130}} \]