# Question #e0a62

Aug 6, 2017

I got $25 m$

#### Explanation:

We could use the relationship from Kinematics:

${v}_{f}^{2} = {v}_{i}^{2} + 2 a d$

that, with your data for the first part, gives:

${15}^{2} = {30}^{2} + 2 a \cdot 75$

solving for $a$:

$a = - 4.5 \frac{m}{s} ^ 2$

we use this acceleration in ${v}_{f}^{2} = {v}_{i}^{2} + 2 a d$ again for the second part where the final velocity will be zero and initial $15 \frac{m}{s}$:

${0}^{2} = {15}^{2} - 2 \cdot 4.5 \cdot d$

$d = 25 m$