# Can someone help explain the reasoning behind this question?

Apr 19, 2016

10.12 m

#### Explanation:

You know the intial velocity ($u$) = $3.2 m {s}^{- 1}$

and, the final velocity ($v$) = $9.7 m {s}^{- 1}$

You also know the acceleration ($a = g \sin \theta$) = 9.8 *sin25°ms^(-2)=4.14ms^(-2)

if you apply the conservation of energy, you have:

${v}^{2} = {u}^{2} + 2 a s$, where s is the distance travelled.

hence, $s = \frac{1}{2 a} \left({v}^{2} - {u}^{2}\right) = \frac{1}{2 \cdot 4.14} \cdot \left({9.7}^{2} - {3.2}^{2}\right) m = 10.12 m$