In which situation would the moment arm be the greatest? A muscle is attached 3
ID: 1998691 • Letter: I
Question
In which situation would the moment arm be the greatest?
A muscle is attached 3 cm from the joint and its force is perpendicular to the bone.
A muscle is attached 4 cm from a joint and its force is parallel to the bone.
A muscle is attached 3 cm from a joint and its force is at 45 degrees to the bone.
A.A muscle is attached 3 cm from the joint and its force is perpendicular to the bone.
B.A muscle is attached 4 cm from a joint and its force is parallel to the bone.
C.A muscle is attached 3 cm from a joint and its force is at 45 degrees to the bone.
Explanation / Answer
A muscle is attached 3 cm from the joint and its force is perpendicular to the bone ,
the moment arm = F(3 cm ) sin 90 = F(3cm)
A muscle is attached 4 cm from a joint and its force is parallel to the bone,
the moment arm = F(4 cm) sin 0 = 0
A muscle is attached 3 cm from a joint and its force is at 45 degrees to the bone ,
the moment arm = F(3cm) sin 45
Therefore option(A) is correct.