a 10 kg block moves along an incline 30 degrees above the horizontal?

Question

the center of gravity of the box is elevated 3 m above the ground, the kinetic energy decreases 50 J. The only forces reacting upon the object is force R ( parallel to the incline) and the force of gravity. the incline is frictionless and g=9.841. calculate the magnitude of R

Answer 1

The gain in potential energy is
10*9.841*3
or
295.23 J

the delta KE is -50 J, therefore R is pushing the block up the incline and worked a total of
245.23 J
this is d*R
the distance is d=sin(30)*3
or 1.5
R=245.23/1.5
R=197 N

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