Block pulled on horizontal surface -w/friction-

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bdragons
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Homework Statement


A box weighing 80N is pulled along a horizontal surface by a force of 15 N which is directed at 20° above the horizontal. If the box started from rest and the coefficient of friction is 0.15, find the kinetic energy and velocity of the box after it traveled a distance of 10 m.

Homework Equations


Normal force= W-Tsinθ
Frictional force=μk x Normal force

The Attempt at a Solution


First I looked for normal force which turns out as 74.87 then frictional force which is 11.23 after that, I don't get how to find velocity. I just need final velocity at this point to get average velocity=velocity then having V, I could solve for K.E.
 
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Force accelerates the box's speed.
It has a speed of 0m/s in the beginning.
[itex]x = x_0 + v_0t + 0.5at^2[/itex]
[itex]x = 0.5at^2[/itex]
On the other hand
[itex]v_{end} = v_0 + at[/itex]
[itex]v_{end} = at[/itex]
Should be all the info you need. Think about it.
 
would just like to clear the following things:
-what does x,x0,v0 stand for? (guessing that 0 there means zero)
-does a stand for acceleration while t is time?
 
They're the basic equations of motion.
x = total distance
x_0 = distance from origin(usually 0 unless origin is set somewhere else than on the system you're investigating)
v_0 = speed the system has when you begin investigating it
a = acceleration
t = time
 
If you know the net force F moves the block, acting in the direction of motion, then the work done on the block moving it distance d is given by F*d. Where does that work end up (how is it expressed in the system)?