Question

The stopping distance of a car, D, as a function of its speed, V, is given by the formula D=2V, where 2 is a constant dependent on the specific car and road conditions. Suppose a car traveling at 70 mph requires 177 feet to stop. Find the constant 2, and use it to approximate the stopping distance for this car traveling at 90 mph.

A. 2=2.5, Stopping distance at 90 mph is 225 feet
B. 2=1.5, Stopping distance at 90 mph is 135 feet
C. 2=3, Stopping distance at 90 mph is 270 feet
D. 2=2, Stopping distance at 90 mph is 180 feet

Answer 1

The constant 2 in the equation D=2V can be found by substituting the given values. The stopping distance for a car traveling at 90 mph can be approximated using this constant.

Step-by-step explanation:

The stopping distance of a car, D, as a function of its speed, V, is given by the formula D=2V. In this equation, 2 is the constant that represents the relationship between the car's speed and the stopping distance. To find the value of this constant, we can use the given information. We know that when the car is traveling at 70 mph, the stopping distance is 177 feet. Substituting these values into the equation, we get 177=2*70. Solving for the constant, we find that 2=2.53.

To approximate the stopping distance for this car traveling at 90 mph, we can use the value of the constant 2.53. Substituting 90 for V in the equation D=2V, we get D=2*90=180 feet. Therefore, the correct answer is A. 2=2.53, and the stopping distance at 90 mph is 180 feet.