If the man pushes with a force of 1005N, the box will slide up the ramp at a rate of 1.1m/s². How much normal force is acting on the box?

Nov 24, 2015

I may be wrong but I think that you need one additional information (the mass perhaps?).

Explanation:

Consider the diagram:

Where:
$F = 1005 N$

From Newton`s Second Law, $\Sigma \vec{F} = m \vec{a}$, for $x$ and $y$ directions:
$\left\{\begin{matrix}F - {w}_{x} = m {a}_{x} \\ N - {w}_{y} = 0\end{matrix}\right.$ where ${a}_{x} = 1.1 \frac{m}{s} ^ 2$

$1005 - m g \sin \left(\alpha\right) = 1.1 m$
$N = m g \cos \left(\alpha\right)$
The problem here is that I have three unknowns, $m , \alpha \mathmr{and} N$ and only 2 equations!