Question

Jayden was on his motorcycle approaching a traffic light. As the light turned red he began to brake, deceleration was at a constant rate of 5.35 m/s2 for 50.0 m where he stopped. What was Jayden’s initial velocity before he began to brake? How long in seconds did it take Jayden to stop?

Answer 1

Answer:Initial velocity= 23.1m/s, Time taken=4.3s

Explanation:Final velocity (v)= 0m/s

(because he stopped as the light turned red)

a= -5.35m/s2(minus sign indicates that it is decelerating)

Distance= 50m

Now,v2- u2=2as

0-u2= 2*(-5.35)*50

-u2 = -535

u= root 535= 23.1

Therefore initial velocity= 23.1m/s

Now,v= u+at

0= 23.1 + (-5.35)t

-23.1= -5.35t

t= 23.1/5.35

t= 4.3s