Calculate the torque about the elbow

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In summary, the conversation discusses an exercise called "curing weights" where athletes hold their arm steady against their body and pull a weight to their chest. The conversation then goes on to calculate the torque about the elbow caused by a 40 pound weight at a 55 degree angle, using the formula torque= F s sin(). However, the length of the arm (s) is not given and may need to be estimated to fully solve the equation. The force is also expressed in kilograms and then converted to newtons. The conversation ends with a suggestion to use 178 KN for the force, but this is not necessary.
  • #1
dg_5021
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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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  • #2
I suppose you need to estimate the length of an ordinary arm and calculate the torque accordingly.
 
  • #3
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.
 

What is torque?

Torque is the measure of the force that can cause an object to rotate about an axis. It is calculated by multiplying the force applied to the object by the distance from the axis to the point where the force is applied.

What is the axis of rotation for the elbow?

The axis of rotation for the elbow is the center of rotation of the elbow joint, which is located at the intersection of the humerus, radius, and ulna bones.

How do you calculate the force for torque about the elbow?

To calculate the force for torque about the elbow, you need to first determine the distance from the axis of rotation to the point where the force is applied. Then, you can use the formula torque = force x distance to calculate the torque.

What are the units for torque?

The SI unit for torque is Newton-meters (N*m). However, it can also be expressed in other units such as foot-pounds (ft*lb) or inch-pounds (in*lb).

Why is calculating torque about the elbow important?

Calculating torque about the elbow is important because it helps us understand the forces acting on the elbow joint. This information is crucial for preventing injuries and designing exercises or equipment for physical therapy or sports training.

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