How Does Kinetic Friction Affect Acceleration and Speed of a Block?

AI Thread Summary
To determine the speed of a 4.94 kg block being pulled by a force of 12.1 N at a 15° angle, the kinetic friction coefficient of 0.100 must be considered. The acceleration can be calculated using the equation F=ma, factoring in the horizontal component of the applied force and the opposing force of kinetic friction. The normal force is affected by the vertical component of the applied force, which alters the frictional force acting on the block. After calculating the acceleration, the speed can be found by multiplying the acceleration by the time of 3.70 seconds. Understanding the free body diagram is crucial for accurately resolving the forces involved.
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Homework Statement



A 4.94 kg block located on a horizontal floor is pulled by a cord that exerts a force F = 12.1 N at an angle θ = 15.0° above the horizontal, as shown in the Figure.

The coefficient of kinetic friction between the block and the floor is 0.100. What is the speed of the block 3.70 s after it starts moving?


Homework Equations


F=ma


The Attempt at a Solution



I understand to find the acceleration I need F=ma, so cos(15)12.1 = 4.94(a).
And I know that when I find the (a), I can just * the 3.7 seconds. I just don't know where to fit in the kinetic friction of 0.1. I'm guessing it has to be minus from the total F but something isn't going right, any ideas, thanks
 
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Erm not exactly...draw the free body diagram and resolve the x and y component of the force applied and you can find the static friction by using uN where u is static coefficient and N is the normal force on the block.
 
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