Final answer:
The stopping distance for a car going 70 mph would be approximately 387 feet, given favorable road conditions and a prompt reaction time. This distance is an estimate based on a similar scenario where a car traveling at a slightly lower speed can decelerate at a rate of 7.00 m/s² on dry pavement.
Step-by-step explanation:
To determine how many feet a car going 70 mph travels before it comes to a stop once the brakes have been applied, we need to consider factors such as the car's initial velocity, the deceleration rate of the car, and driver reaction time. It's difficult to give an exact number without specific information about the road conditions and the car's deceleration rate, but we can provide an estimate.
Using the provided reference information, we can draw parallels from the example of a car traveling at 30.0 m/s, which is approximately equivalent to 67 mph. The example states that on dry concrete, a car can decelerate at a rate of 7.00 m/s², and on wet concrete, it can decelerate at a rate of 5.00 m/s². Additionally, a reaction time of 0.500 s is factored into the calculation.
Given this information, the choice that most closely approximates a reasonable stopping distance for a car going 70 mph under good conditions would be option d) 387 feet. This assumes a prompt reaction time and favorable road conditions. The stopping distance would be shorter on dry concrete compared to wet concrete due to the higher deceleration rate possible on dry surfaces.