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1 year ago

Help Please!Could someone help me out with this one?

Physics

1 answer:

Radda [10]1 year ago

5 0

mass of the chair = 25 kg

Force required to start the motion = 165 N

Force required to maintain the motion = 127 N

part a)

when we applied the force to just start the motion then it is just equal to the limiting friction force

$F_s = F$

now as we know that

$\mu_s mg = 165$

$\mu_s * 25 * 9.8 = 165$

$\mu_s = \frac{165}{25*9.8}$

$\mu_s = 0.67$

PART b)

when object has started motion then to maintain its motion we need external force to balance kinetic friction

$F_k = F$

now as we know that

$\mu_k mg = 127$

$\mu_k * 25 * 9.8 = 127$

$\mu_k = \frac{127}{25*9.8}$

$\mu_k = 0.52$

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