Answer:
Explanation:
To find the vertical and horizontal components of the muscular force, we can use trigonometry. Let F be the force exerted by the muscle, and θ be the angle it makes with the horizontal.
Horizontal component of the force Fx = F cos θ
Vertical component of the force Fy = F sin θ
Given that the muscular force is 75kg and the angle of pull is 15 degrees, we have:
Fx = 75kg x cos(15) = 72.62 kg (approx.)
Fy = 75kg x sin(15) = 19.34 kg (approx.)
To determine which force would be responsible for the rotation of the bone around the joint, we need to consider the torque or moment created by the force. The torque is given by the force times the lever arm, which is the perpendicular distance from the line of action of the force to the axis of rotation. In this case, the axis of rotation is the joint, and the lever arm is the distance from the joint to the point where the muscle attaches to the bone.
The torque due to the horizontal component of the force is zero, since it acts perpendicular to the lever arm. The torque due to the vertical component of the force is:
Torque = Fy x d
where d is the lever arm. If we assume that the lever arm is 5 cm, we have:
Torque = 19.34 kg x 0.05 m = 0.967 Nm
Therefore, the vertical component of the force would be responsible for the rotation of the bone around the joint.
To determine which force would cause a compressive force at the joint, we need to consider the direction of the force. A force that acts perpendicular to the bone would cause compression at the joint. In this case, the vertical component of the force is perpendicular to the bone, while the horizontal component is parallel to it. Therefore, the vertical component of the force would cause a compressive force at the joint.
Here is a diagram of the situation:
|\
Fy | \ /|
| \ / |
| \ / |
| \ / |
| \ / |
| \/ |
| /\ |
| / \ |
| / \ |
| / \ |
| / \ |
| / \|
|/______\
Fx
In the diagram, Fx is the horizontal component of the force, Fy is the vertical component of the force, and the bone is represented by the vertical line. The angle θ is the angle between the force and the horizontal. The lever arm d is the distance between the joint and the point where the muscle attaches to the bone.