Science Passage 1 (Questions 1-5)

Students used 2 methods to calculate D , car's total stopping distance; D is the distance a car travels from the time a driver first reacts to an emergency until the car comes to a complete stop.

In Method 1, R is the distance a car travels during a driver's assumed reaction time of 0.75 sec, and B is the average distance traveled once the brakes are applied.  Method 2 assumes that D = initial speed in ft./sec. x 2 sec. 

Table 1 lists R, B, and D for various initial speeds, where D was computed using both methods.  Figure 1 contains graphs of D  versus initial speed for Method 1 and Method 2.