A 51 kg box is being pushed a distance of 7.0 m across the floor by a force P whose magnitude is 143 N. The force P is parallel to the displacement of the box. The coefficient of kinetic friction is 0.25. Determine the work done on the box by each of the four forces that act on the box. Be sure to include the proper plus or minus sign for the work done by each force.
(a) Applied force
(b) Frictional force
(c) Normal force
(d) Gravity
(a) Applied force
(b) Frictional force
(c) Normal force
(d) Gravity
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51 x 9.8 = 499.8N. weight.
a) (143 x 7) = 1,001 joules.
b) Friction force = (499.8 x 0.25) = 124.95N.
Work done = (124.95 x 7) = 874.65 joules, opposite direction to (a).
c) 0 work done by 499.8N. force applied up from floor.
d) 0 workdone by 499.8N. gravitational force applied down on floor.
a) (143 x 7) = 1,001 joules.
b) Friction force = (499.8 x 0.25) = 124.95N.
Work done = (124.95 x 7) = 874.65 joules, opposite direction to (a).
c) 0 work done by 499.8N. force applied up from floor.
d) 0 workdone by 499.8N. gravitational force applied down on floor.