Simple Torque Problem: Find the Torque and Force Exerted by Triceps Muscles

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The discussion revolves around calculating the torque and force exerted by triceps muscles while accelerating a 3.6 kg ball at 7.0 m/s². The forearm length is 30 cm, and the calculations yield a torque of 0.756 Nm and a force of 25.2 N. The solution approach involves using the equations τ = Iα and τ = R x F, with the participant correctly applying the formulas. An alternative method suggested is to first calculate the force using F = ma before determining the torque. The calculations and methodology presented are confirmed to be correct.
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There is no answer in the back of the textbook to the problem I did. I'm self-studying, so can someone check if my answer is correct.

Homework Statement


The forearm accelerates a 3.6 kg ball at 7.0 m/s2 by means of the triceps muscle. The forearm is 30 cm long and is perpendicular triceps muscle. Calculate the torque and the force exerted by triceps muscles.

Homework Equations

\tau = I\alpha

\tau = R x F

The Attempt at a Solution



a = 7.0 (m/s2), m = 3.6 (kg), r = .03 (m)
\tau = I\alpha , \alpha = a/r, I = m*r2
= m*r2\alpha
= m*r*a
= 3.6*.03*7
\tau = .756

\tau = r * F
F = \tau/r
F = .756/.03
F = 25.2

Homework Statement


Homework Equations


The Attempt at a Solution

 
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Your answers are correct. Though you could have found the force (ma) first and then the torque (rF)
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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