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Thank you We sneak and here's your shmoop du jour

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Brought to you by static friction Some materials have a

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low coefficient of friction And with other materials like say

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us in our bed almost no amount of force can

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make a move All right twenty kilogram boxes dropped onto

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his surface with a static friction coefficient of zero point

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five in a kinetic friction coefficient of zero point two

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a force of eighty newtons is applied to the box

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What is the acceleration of the box And here the

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potential answers in meters per second squared All right well

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we here at shmoop love information We crave it but

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there is such a thing as too much information For

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example one time we told a friend that we still

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sleepin batman pajamas And that was definitely a t m

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i And this question wealth a little tricky because it

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has too much information also but let's tackle the math

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First first thing we have to do is get this

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box moving And to do that we need to overcome

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the force of static friction Well to calculate that force

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we just multiply the normal force in this case mass

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Times Gravity by the coefficient of friction so here's the

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equation Once we have the numbers we need we plug

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him in and find that the force of friction is

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one hundred newtons Since the force acting on the box

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is only eighty new queens the box is going nowhere

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fast so the correct answer is just option a zero

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meters per second squared and sense is not gonna budge

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The kinetic friction coefficient doesn't matter No movement equals no

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kinetic friction That's What we mean by t m i

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