posted by Vishnu on .
An athlete at the gym holds a 4.33 kg steel ball in his hand. His arm is 68.7 cm long and has a mass of 4.69 kg. What is the magnitude of the torque about his shoulder if he holds his arm straight out to his side, parallel to the floor?
Torque = massball x length + massarm x length/2
= 4.33 kg x 0.687 m + 4.69 kg x 0.687 m/2
= 7.66472 x 1.374
= 10.5 N
Why is my answer incorrect?
ooops. Masses need to be multiplied by g, to get FORCE.