How Do I Calculate Kinetic Friction and Acceleration in These Physics Problems?

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To calculate kinetic friction and acceleration in physics problems, it's essential to start with free body diagrams to visualize forces acting on the objects. For the first problem, the coefficient of kinetic friction can be determined using the frictional force equation F = uN, where N is the normal force. In the second problem, the net force acting on the crate can be expressed as Fcos(θ) - Uk(mg - Fsin(θ)) = ma. Understanding these fundamental equations allows for solving the problems effectively. Proper application of these principles leads to accurate calculations of kinetic friction and acceleration.
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Homework Statement



(1)When mass M is at the position shown, it is sliding down the inclined part of a slide at a speed of 1.95 m/s. The mass stops a distance S2 = 1.85 m along the level part of the slide. The distance S1 = 1.25 m and the angle theta = 35.9 degrees. Calculate the coefficient of kinetic friction for the mass on the surface.

(2)A man pulls a crate of mass 73.0 kg across a level floor. He pulls with a force of 188.0 N at an angle of 31.0° above the horizontal. When the crate is moving, the frictional force between the floor and the crate has a magnitude of 114.0 N. If the crate starts from rest, how fast will it be moving after the man has pulled it a distance of 2.90 m?


Homework Equations


(1) I'm not really sure how to do 1 at all, I have looked through my book and notes and can't see any solution to the problem
(2) I used the formula Fcos(o)-Uk(mg-Fsin(o))=ma


The Attempt at a Solution


(2) I used the formula Fcos(o)-Uk(mg-Fsin(o))=ma
 
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I suggest you post this on the physics forum...
 
Start with the free body diagrams. Once you can do that, the equations you need are F=uN (Frictional force) and F=ma. All other so called formulas (in this context) are simple expressions of these two basic equations.
 
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