Question

I need help on how to do this problem.

Many thanks!

Answer 1

Explanation:

First, we. need to convert the initial velocity of 85 km/hr into m/s:

$85\:\dfrac{\text{km}}{\text{hr}}×\dfrac{1000\:\text{m}}{1\:\text{km}}×\dfrac{1\:\text{hr}}{3600\:\text{s}}=23.6\:\text{m/s}$

Next, we're going to use the equation below:

$v^2 = v_0^2 + 2ax$

Since $v=0\:\text{and}\:a = -1.3\:\text{m/s,}^2$ we can solve for the distance x:

$x = -\dfrac{v_0^2}{2a} = -\dfrac{(23.6\:\text{m/s})^2}{2(-1.3\:\text{m/s}^2)}$

$\:\:\:\:\:\:\:=214.2\:\text{m}$