Question

A body moving with uniform acceleration has a velocity of $-9 \,cm / s$ when its $x$ co-ordinate is $3.00\,cm$. If its $x$ coordinate $3\, s$ later is $-6\, cm$, what is the magnitude of its acceleration $\left(\right.$ in $\left.cm / s ^{2}\right)$ ?

Answer 1

$u=-9 \,cm / s$
$s=-6-3=-9 \,cm$
$t=3 \,s$
$s=u t+\frac{1}{2} a t^{2}$
$-9=-9 \times 3+\frac{1}{2}+a \times 3^{2}$
$a=4 \, cm / s ^{2}$