An object with a mass of #2 kg# is on a plane with an incline of #pi/8 #. If the object is being pushed up the plane with # 8 N # of force, what is the net force on the object?

1 Answer
Feb 13, 2018

#"please see the explanation section."#

Explanation:

  • drawing a free-body diagram will make it easier to understand.
  • blue and red dotted lines will be useful to separate the weight of the object from the components.

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  • The vector drawn with green symbolizes the weight of the body.

#G=mg=2*9.81=19.62N#

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  • we now have to find the components of the weight on the red and blue axes.

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#G_x=mg*cos theta=2*9.81*cos(pi/8)=18.13 N#

#G_y=mg*sin (theta)=2.9.81*sin (pi/8)=7.51N#

  • The blue vector is acting vertically. We know that the inclined plane will react against the effect(Newton's third law).

#N=-G_y=-mg*cos theta#
#N+(-G_y)=0#

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  • now,let's draw the Force of 8 N and Simplify the look of the diagram.

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  • we need to find the sum of the black and red vectors.

#F_("net")=G_x-F#

#F_("net")=18.13-8#

#F_("net")=10.13N#

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