Nwhich of the following cases is the torque about the shoulder due to the weight of the arm the greatest? case 1: a person holds her arm at an angle of 30o above the horizontal (hand is higher than shoulder). case 2: a person holds her amr straight out parallel to the ground. case 3: a person holds her arm at an angle of 30o below the horizontal (hand is lower than shoulder).

Case 2: A person holds her amr straight out parallel to the ground.

Explanation:

As we know that

Torque Τ given as

T = r x F

T = F r sinθ

θ =Angle between force and distance from force .

If the angle is maximum then the sinθ will be maximum it means that at θ = 90° the torque T will be maximum.

So the case 2 is correct.

Case 2: A person holds her amr straight out parallel to the ground.

when it gains or loses electrons

not too sure thinking all accelerations are pointed down