Two people carry a heavy electric motor by placing it on a light board 1.50 m long. One person lifts at one end with a force of
1 answer:
Answer:
a) The weight of the motor is 1120 N
b) The distance of the center of gravity is 1.71 m
c) The weight of the motor is 920 N
d) The distance of the center of gravity is 1.79 m
Explanation:
a) The expression of the forces acting in the vertical direction is:
wmotor = F1 + F2
F1 = 410 N
F2 = 710 N
wmotor = 410 + 710 = 1120 N
b) The momentum of equilibrium about the center of the gravity is:
F1 * x = F2 * (l - x)
Clearing x:
c) The expression for the forces acting in the vertical direction is:
wboard + wmotor = F1 + F2
wmotor = F1 + F2 - wboard
wmotor = 410 + 710 - 200
wmotor = 920 N
d) The same that b)
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Answer:
<em>The normal force is perpendicular to the displacement</em>
<em>The static friction force produces no displacement</em>
Explanation:
Work Done By Special Forces
The work is a physical magnitude that measures the dot product of the force applied to an object by the displacement it produces in it.
It can be written in its scalar version as
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Since in this case, there is no displacement, d=0, and the work is