Answer to Question #317212 in Mechanics | Relativity for nnn

Question

a box starting from rest and slides down an inclined plane with uniform acceleration and travels 9 m in 3 s. in what time from rest will it acquires a velocity of 24m/s down the plane

Answer 1

Explanations & Calculations

• Since the acceleration is uniform, apply $\small s = ut+\frac{1}{2}at^2$ down the incline for the box's motion.

$\qquad\qquad \begin{aligned} \small 9\,m&=\small 0+0.5(a)(3\,s)^2\\ \small a&=\small 2\,ms^{-2} \end{aligned}$

• With this acceleration apply $\small v=u+at$ the same way done in the previous step

$\qquad\qquad \begin{aligned} \small 24\,ms^{-1}&=\small 0+(2\,ms^{-2})(T)\\ \small T&=\small 12\,s \end{aligned}$