Question

A car is traveling at 13.0 m/s, and the driver sees a traffic light turn red. After 0.590 s (the reaction time), the driver applies the brakes, and the car decelerates at 8.00 m/s2. What is the stopping distance of the car, as measured from the point where the driver first sees the red light?

Answer #1

**Gien**

**car traveling at 13.0 m/s and driver applied the brakes
after 0.59 s so**

**the displacement covered in 0.59 s
is **

**s1 = 0.59*13 m = 7.67 m**

**and**

**after applying the brakes car decelerating with 8 m/s2
after some time comes to rest by covering a distance of
s2**

**the distance covered before come to rest
is **

**using equations of motion**

**v^2 - u^2 = 2*as**

**finally car comes to rest so t v = 0**

**u = 13 m/s**

**a = -8 m/s2**

**0-13^2 = 2*8*s2**

**solving for s2 , s2 = 10. 5625 m**

**the total distance covered by the car before come to
rest is **

**S = s1+s2 = 7.67+10.5625 m = 18.2325 m**

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