How Fast Does a Block Slide Down a Ramp with Friction?

[vic05]

Homework Statement

Block slides down a 1 meter ramp at a 30 degree angle. The coefficient of kinetic friction is 0.4
what is the block's speed at the bottom of the ramp?

Homework Equations

kineticFriction force = coefficient of friction X normal Force

normal Force = force of gravity + mass*acceleration

The Attempt at a Solution

I've tried the problem but i get stuck of finding the normal force required to find the kinetic friction force. Can someone guide me a little bit please... thank you in advanced

 

[Basic_Physics]

The normal force and the component of the weight of the block need to cancel each other out.

 

[vic05]

solved! the professor gave us a formula but I copied it wrong... just for reference the formula which gave acceleration was a = g[sinO - UkcosO]

 

[Basic_Physics]

Physics not about memorizing formulas, it is about deriving them from first principles, so can you?