So is .70 m not the center of gravity. I'm so confused ...ehild said:This would by right if all mass of the arm were concentrated in the hand.
ehild
housemartin said:theta is not zero, it is 90 degrees. And 0.7 m is not the center of gravity. If you have a uniform stick, which length is 0.7 m and has a 4 kg mass, where is then its center of mass?
housemartin said:because you need to calculate torque about the shoulder (well topic name says about shoulder, but in problem statement you say about the arm...). In order to do so, you must take distances from shoulder (its like shoulder is your coordinates starting point), and ball is 0.7 m away from the shoulder.
Torque about the shoulder is a measure of the rotational force applied to the shoulder joint. It is created by the muscles and tendons surrounding the shoulder and is necessary for performing movements such as lifting, throwing, and reaching.
To calculate torque about the shoulder, you need to know the force being applied and the distance from the force to the center of rotation (shoulder joint). The formula for torque is torque = force x distance.
The amount of torque about the shoulder can be affected by several factors, including the strength and size of the muscles, the angle of the joint, and the position of the body in relation to the force being applied.
Torque about the shoulder is important because it allows us to perform a wide range of movements and activities. Without sufficient torque, we would not be able to lift heavy objects, throw a ball, or even reach for something on a high shelf.
To improve torque about the shoulder, it is important to strengthen the muscles and tendons surrounding the shoulder joint. This can be done through exercises that target the shoulder muscles, such as shoulder presses, rows, and lateral raises. Proper form and technique during these exercises can also help improve torque about the shoulder.