# physics

A 4.170 kg block of wood rests on a steel desk. The coefficient of static friction between the block and the desk is μs = 0.505 and the coefficient of kinetic friction is μk = 0.255. At time t = 0, a force F = 12.7 N is applied horizontally to the block. State the force of friction applied to the block by the table at the following times:
t=0 and t>0

1. 👍 2
2. 👎 0
3. 👁 4,456
1. Friction = uN

N=mg so

F=umg

F at t(0) = (.505)(4.17 kg)(9.8 m/s^2)

F at t>0 = (.255)(4.17 kg)(9.8 m/s^2)

1. 👍 0
2. 👎 8
2. idk

1. 👍 3
2. 👎 18

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