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)
 
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