M*g = 3.5 * 9.8 = 34.3 N. = Wt. of block = Normal force(Fn).
Fp = 15*Cos40 = 11.5 N. = Force parallel with the surface.
1. Fk = u*Fn = 0.25 * 34.3 = 8.58 N.
2. Fp-Fk = M*a. a = ?.
A 3.5 kg block is pushed along a horizontal floor by a force of magnitude 15 N at an angle 40° with the horizontal (Fig. 6-19). The coefficient of kinetic friction between the block and the floor is 0.25. Calculate the magnitudes of (i) the frictional force on the block from the floor
and (ii) the block’s acceleration.
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