A Playground Slide and Some Friction

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The discussion revolves around calculating the acceleration of a child sliding down a playground slide inclined at 28.0° with a coefficient of kinetic friction of 0.415. The initial equations set up the forces acting on the child, but a mistake was identified in the calculations, specifically the omission of the gravitational constant (g). The corrected formula for acceleration includes g, leading to the final equation: a = (9.8sin28) - (9.8 x 0.415 cos28). This correction resulted in a more accurate calculation of the child's acceleration down the slide. The conversation highlights the importance of careful attention to detail in physics problems.
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A child goes down a playground slide that is inclined at an angle of 28.0° below the horizontal. Find the acceleration of the child given that the coefficient of kinetic friction between the child and the slide is 0.415

Heres what I have so Far:
F - fk = ma
mgsin0 - MkN = ma
mgsin0 - Mkmgcos0 = ma
gsin0 - mkcos0 = a

so by this,

a = 9.8sin28 - .415cos28
= 4.2343

I cannot figure out what I am doing wrong here


thanks friends
 
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a = 9.8sin28 - .415cos28

There should be a g in there. You dropped it somewhere along the way.
 
So, just because it is my last submission on this problem the answer should then be:

a = (9.8sin28) - (9.8 x .415 cos28)

such a stupid mistake...thanks
 
Seems reasonable to me.
 
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