contestada

1. A block with mass 20 kg is
sliding up a plane (Ukinetic=0.3,
inclined at 10°) at a speed of
2 m/s to the right (positive
X-direction). How far does it
go up along the plane before
it comes to rest momentarily?

Respuesta :

Answer: 0.435 m

Explanation:

Given

mass m=20 kg

initial speed u=2 m/s

coefficient of kinetic friction [tex]\mu_k=0.3[/tex]

deceleration which opposes the motion is given by

[tex]\Rightarrow a=g\sin \theta+\mu_kg\cos \theta\\\Rightarrow a=g(\sin \theta +\mu_k\cos \theta)[/tex]

[tex]\Rightarrow a=9.8(\sin 10^{\circ}+0.3\times \cos 10^{\circ})\\\Rightarrow a=4.59\ m/s^2[/tex]

using [tex]v^2-u^2=2as[/tex]

[tex]\Rightarrow s=\dfrac{2^2}{2\times 4.59}=0.435\ m[/tex]