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sugz
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Homework Statement
The 45-kg boy has taken a running jump from the upper surface and lands on his 5-kg skateboard with a velocity of 5 m/s in the place of the figure as shown. If his impact with the skateboard has a time duration of 0.05 s, determine the total normal force N exerted by the ground on the skateboard wheels during the impact. The speed is 30 degrees below the horizontal.
a. 1.73 kN b. 2.22 kN c. 2.74 kN d. 2.44 kN e.None of these
Homework Equations
(Fnet)(delta t) = (delta p) = mvf-mvi, where vi=0
vfx=(-1)*(5sin30)
vfy=5cos30
The Attempt at a Solution
Fx = mvf/(delta t)
Fx = [(50)(5)*cos(30)]/0.05 = 4330.12 N
Fy = mvf/(delta t)
Fy = [(50)(5)*(-1)*sin(30)]/0.05 = -2500
The force equations for the boy on the skateboard:
(Fnet)y=-2500=Fn-mg
=-2500+(50)(9.81)
=-2009.5N
Is my answer correct? This does not seem to be any of the multiple choices give. If incorrect, please help me find where I made the mistake.
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