approximately what force,FM must the extensor muscle in the upper arm exert on the lower arm to hold a 7.6kg shot put? assume th

Question

olchik [2.2K]

2 years ago

11

approximately what force,FM must the extensor muscle in the upper arm exert on the lower arm to hold a 7.6kg shot put? assume th

e lower arm has a mass of 2.8kg and it's CG is 11.6cm froom the pivot point.

Physics

1 answer:

MAXImum [283] · Answer 1 · 2022-03-16T11:28:11+03:00

Lets do the sum of the forces about the elbow joint.

Fm = Force of Muscle; Fe = Force Elbow; Fb = Force Ball

Sum Force about Joint = (-2.5)Fm + 12.5Fe + 30Fb = 0

(-2.5)Fm + 12.5(2.8) + 30(6.9) = 0

Fm = 96.8kg

Fm = 96.8 * 9.8 = 948.6N

Do you understand why the -2.5 is negative?
<span> Because I put the origin at the joint. So when you go left it is negative and when you go right it is positive. </span>