Block pulled on horizontal surface -w/friction-

AI Thread Summary
A box weighing 80N is pulled on a horizontal surface by a 15N force at a 20° angle, with a coefficient of friction of 0.15. The normal force is calculated as 74.87N, and the frictional force is determined to be 11.23N. The discussion focuses on finding the final velocity and kinetic energy after the box travels 10m, starting from rest. Key equations of motion are referenced, including those for distance, initial velocity, acceleration, and time. Clarifications are sought regarding the variables used in the equations and the work-energy relationship in the system.
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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.
x = x_0 + v_0t + 0.5at^2
x = 0.5at^2
On the other hand
v_{end} = v_0 + at
v_{end} = at
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)?
 
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