Question

An accident investigator measured the skid marks of one of the vehicles involved in an accident. The length of the skid marks was 84 feet. What was the speed of the vehicle before the brakes were applied?

a. 28 ft/s
b. 14 ft/s
c. 21 ft/s
d. 42 ft/s

Answer 1

The speed of the vehicle before the brakes were applied can be calculated using the skid marks left by the vehicle. The stopping distance can be found by using the formula Stopping Distance = (Initial Velocity^2) / (2 * Deceleration).

Step-by-step explanation:

The speed of the vehicle before the brakes were applied can be calculated using the skid marks left by the vehicle. The length of the skid marks can be used to find the stopping distance of the vehicle. The formula to calculate the stopping distance is: Stopping Distance = (Initial Velocity^2) / (2 * Deceleration)

From the given information, the length of the skid marks is 84 feet. Assuming the vehicle started with an initial velocity of V ft/s, the deceleration can be calculated using the coefficient of friction between the tires and the road. Then, the stopping distance can be calculated and equated to 84 feet to solve for the initial velocity of the vehicle. The correct answer is d. 42 ft/s.