In a tractor-pull competition, a tractor applies a force of 1.3kN to the sled, which has mass 1.1x 10^4 kg. At that point, the coefficient of kinetic friction between the sled and the ground has increased to 0.80. What is the acceleration of the sled? What is the significance of the sign of the acceleration?

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anonymous · Answer

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i get right along + so 
$$F-f=ma $$
$$f=\mu _{k}mg$$
$$a=(F-\mu _{k}mg)/m$$