What type of equilibrium relates to the force of gravity?

Static equilibrium refers to the type of balance that relates to the force of gravity. In this context, it involves the position of the body when it is at rest, and how the vestibular system detects changes in the position of the head relative to the gravitational pull. This system, primarily located in the inner ear, is responsible for sensing the orientation of the body in space while at rest, which is critical for maintaining postural stability and balance.

Static equilibrium is specifically concerned with the orientation of the body in a stationary position, as opposed to dynamic equilibrium, which involves movement and the detection of motion changes. Rotational equilibrium deals with the balance of forces during spinning motions or when the head is in rotational movement. Linear equilibrium pertains to linear motion along a straight path, which is not directly related to the gravitational force acting on a stationary body. Therefore, static equilibrium is the correct answer, as it encompasses how gravity affects the body's balance when not in motion.