Question

While a roofer is working on a roof that slants at 38.0 ∘ above the horizontal, he accidentally nudges his 95.0 n toolbox, causing it to start sliding downward, starting from rest. part a if it starts 4.60 m from the lower edge of the roof, how fast will the toolbox be moving just as it reaches the edge of the roof if the kinetic friction force on it is 20.0 n ?

Answer 1

1. Find all the forces on the toolbox
2. Use the total force to find the total acceleration
3. Use the acceleration to find the final velocity by combining these equations:
$x = \frac{1}{2} at^2 =\ \textgreater \ t^2 = \frac{2x}{a} \\ v = at =\ \textgreater \ t^2 = \frac{v^2}{a^2} \\ \\ v = \sqrt{2xa}$