A young girl sits at the edge of a dock by the bay, dipping her feet in the wate
ID: 2295954 • Letter: A
Question
A young girl sits at the edge of a dock by the bay, dipping her feet in the water. At the instant shown in the figure(Figure 1) , she holds her lower leg stationary with her quadriceps muscle at an angle of 39 ? with respect to the horizontal.
Use the information given in the figure, plus the fact that her lower leg has a mass of 3.9kg , to determine the magnitude of the force, FQ, exerted on the lower leg by the quadriceps.
Express your answer using two significant figures.
FQ = ??? N
Knee joint 29° 12 cm Lower leg cm 39°Explanation / Answer
I summed up the torques in the system using torque = rFsin(theta) and then solved for FQ.
torque = (.12m)FQsin(29) - (.35m)(3.9kg)(9.8)sin(51) = 0
Simple algebra from there.
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.