Calculate the torque about the elbow

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To calculate the torque about the elbow from a 40-pound weight at a 55-degree angle, the torque formula is used: torque = F * s * sin(angle). The force is converted from pounds to grams and then to Newtons, resulting in approximately 178 kN. The variable 's' represents the distance from the elbow to the point where the force is applied, which is not provided in the problem. Without a specific length for 's', the torque can only be expressed in terms of this variable. Estimating an average arm length can help in calculating a numerical value for torque.
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Athletes sometimes do an exercise called "curing weights." This exercise consists of holding the arm from the shoulder to the elbow steady and snug against the body while pulling a weight to the chest. Calculate the torque about the elbow caused by a 40 pound weight that makes an angle of 55 degrees with respect to the body.

i know the formula is torque= F s sin()
I found the force by coverting pound 40pounds/2.2046kg= 18.144kg x 1000g= 18144 g x 9.81m/s =177993force

torque= F s sin(55)= (18144g)(9.81 m/s2) (s) sin(55)=

but what is s they don't give me the s. do i have to use other formula? am confused? please help
 
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I suppose you need to estimate the length of an ordinary arm and calculate the torque accordingly.
 
Seems to me, if they don't give you a length of the forearm, then you have solved it completely with s left as a variable. Although, I would probably express the force as 178 KN, but that's just me.
 
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