newtons lawz problem need help (1 Viewer)

clicker

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A plastic block slides from rest a distance of 0.70 m down a plank. If there is no friction between the block and the plank which is at an angle of 20o to the horizontal, calculate the velocity of the block when it has reached the bottom of the plank.
 

KFunk

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With a bit of geometry you can work out that the component of the gravity acting on the object down the hill is
gsin(20)= 3.35ms<sup>-2</sup>

Since you know the acceleration will be constant (no friction) you can use v<sup>2</sup>=u<sup>2</sup> +2as [where u=0]
v= &radic;(2as)
=&radic;(4.69)
=2.17 ms<sup>-1</sup>

I hope that's the figure you were looking for.
 

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