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2 years ago

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A 15.4 kg block is dragged over a rough, horizontal surface by a constant force of 182 N acting at an angle of 24◦ above the hor

izontal. The block is displaced 57.6 m, and the coefficient of kinetic friction is 0.135. The acceleration of gravity is 9.8 m/s 2.

1 answer:

Dima020 [189]2 years ago

3 0

Answer:

Explanation:

Considering Work done by friction is asked

Given

mass of block $m=15.4\ kg$

force $F=182\ N$

inclination $\theta =24^{\circ}$

block is displaced by $s=57.6\ m$

coefficient of kinetic friction $\mu _k=0.135$

Friction force $F_r=\mu _kN$

Normal reaction $N=mg-F\sin \theta =15.4\times 9.8-182\sin (24)$

$N=76.9\ N$

Friction Force $F_r=0.135\times 76.9=10.38\ N$

Work done by friction force

$W=f_r\cdot s$

$W=10.38\times 57.6=597.92\ N$

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