Answer:
9.17649955924 m
1.36848639456 seconds
Explanation:
t = Time taken
u = Initial velocity = 30 mi/h
v = Final velocity = 0
s = Displacement
a = Acceleration = -9.8 m/s² (-ve due to deceleration)
[tex]v^2-u^2=2as\\\Rightarrow s=\dfrac{v^2-u^2}{2a}\\\Rightarrow s=\dfrac{0^2-(\dfrac{30\times 1609.34}{3600})^2}{2\times -9.8}\\\Rightarrow s=9.17649955924\ m[/tex]
The distance before reaching the intersection must be at most 9.17649955924 m not less than that.
[tex]v=u+at\\\Rightarrow t=\dfrac{v-u}{a}\\\Rightarrow t=\dfrac{0-\dfrac{30\times 1609.34}{3600}}{-9.8}\\\Rightarrow t=1.36848639456\ s[/tex]
The time to come to a halt is 1.36848639456 seconds
