Question

If a car go from 0 to 60 mi/hr in 8.0 seconds, what would be its final speed after 5.0 seconds if its starting speed were 50 mi/hr?

Answer 1

Answer:

v = 87.57 m/s

Explanation:

Given,

The initial velocity of the car, u = 0

The final velocity of the car, v = 60 mi/hr

The time period of car, t = 8 s

                                         = 0.00222 hr

The acceleration of the car is given by the formula,

                                       a = (v -u) / t

                                           = 60 / 0.00222

                                            = 27027 mi/hr²

If the car has initial velocity, u = 50 mi/hr

The time period of the car, t = 5.0 s

                                         = 0.00139 hr

Using first equations of motion

                                      v = u + at

                                          = 50 + (0.00139 x 27027)

                                          = 87.57 mi/hr

Hence, the final velocity of the car, v = 87.57 mi/hr